"whoever despises the discipline of the church, so as to abstain from warning, correcting, censuring, and yes also separating from participation in the sacraments the evil persons in whose sins he does not participate and whom he does not applaud, sins not with the evil of another, but with his own."

"For this reason, too, whoever despises the discipline of the church, so as to abstain from warning, correcting, censuring, and yes also [(etiam)] separating from participation in the sacraments the evil persons in whose sins he does not participate and whom he does not applaud (although [(etsi)] he tolerates them and the peace of the Church allows for this), sins not with the evil of another, but with his own."

"Quapropter quisquis etiam contempserit ecclesiae disciplinam, ut malos cum quibus non peccat et quibus non fauet desistat monere corripere arguer, etsi talem personam gerit et pax ecclesiae patitur etiam a sacramentorum participation separare, non alieno malo peccat sed suo."

     St. Augustine, Contra epistulam Parmeniani libri tres III.i.2, translation mine.  The Latin as reproduced in Œuvres de Saint Augustine 28 =4th ser. (Traités anti-Donatistes), vol. 1, translated into French by G. Finaert, introduction & notes by Yves M.-J. Congar (Paris:  Desclée de Brouwer, 1963), pp. 386-389 =CSEL 51, ed. M. Petschenig (1908), p. 100, ll. 2 ff.
     What is fascinating about this is that it occurs in a specifically anti-Donatist context in which a concern for "the peace of the Church" (pax ecclesiae) predominates and 1 Cor 5:13 is interpreted in an anti-Donatist fashion as "Drive the evil out of yourselves"!  That this is the case is rendered even more obvious by the paragraph that follows (translated from the French rather than the Latin for the most part, that final sentence only excepted):

Negligence in such a matter is a grave fault in and of itself.  And this is why, if he follows the counsel of the Apostle and removes the evil from his own heart, he will drive out not only the audacity of evil-doing and the weakness of complicity, but also the slowness to correct and the reluctance to punish, while also observing prudence and th[at] obedience to the Master that prevents one from rooting up the good wheat.  If it is with this thought [in mind] that one tolerates the tare in the midst of the wheat, and if he removes from himself the evil of which the tare is guilty [(en ôte de soi-même le mal)], he is not rendered an accomplice of the tare.  [Rather,] he is cognizant of it and judges it by waiting for a while, for he does not know what will happen on the morrow. In this way is punished also whatever a necessary severity is obliged to punish, but by a love severe[, albeit] not hopeless of correction [(et ideo dilectione seruata non sine spe correctionis uindicandum est quidquid etiam cogit necessaria seueritas uindicari)].     

     Congar on p. 741:  "A part of the argumentation [here] bears on the sense given to malum:  with Parmenianus [himself], probably, Augustine understands, then, by this word, not the perverse man [(le mauvais)], but the perversity [(le mal)]. . . . In reality, St. Paul wrote 'le mauvais', τὸν πονηρὸν.  This is true for Deuteronomy as well, which [Augustine] cites:  13:6, 17:7, 22:21.  In Retract[ationes] II.17, . . . Augustine reestablished the true sense according to the Greek, which speaks of the evil man, and not of the evil.  He adds that even in taking the first sense the response to Parmenianus retains its value.  He was in fact dependent on the discipline of the Church, and it is th[e discipline of the Church] that aims to realize the warning of St. Paul."

"the deserving and the undeserving poor". Did Dorothy Day really say exactly this? "The Gospel takes away our right forever to discriminate between the deserving and the undeserving poor."

1st century, Jesus:  "You have heard that it was said, 'You shall love your neighbor and hate your enemy.'  But I say to you, Love your enemies and pray for those who persecute you, so that you may be sons of your Father who is in heaven; for he makes his sun rise on the evil and on the good, and sends rain on the just and on the unjust" (Mt 5:43-45 RSV).

7th century, Maximus the Confessor:  "24. Thus, the one who imitates God by giving alms knows no difference between evil and good or just and unjust in regard to the needs of the body, but distributes to all without distinction according to their need even if he prefers the virtuous person over the wicked because of his good intention.  25. Just as God who is by nature good and free of passion loves all in an equal way as his creatures but glorifies the virtuous man for having become his friend through his intention and has mercy on the wicked out of his goodness and converts him by chastening him in this life, so also does one who is good and without passion through his intention love equally all men--the virtuous because of his nature and good will and likewise the wicked because of his nature and compassion by which he pities the one who is foolish and makes his way in darkness" (Four hundred chapters on love 1.24-25, trans. George C. Berthold, Maximus Confessor:  Selected writings, Classics of Western spirituality (New York:  Paulist Press, 1985), 38).

High Middle Ages:  Irina Metzler, "Disability in the Middle Ages and Cultural History," Werkstatt Geschichte no. 65 (March 2015): 55–65:  "By the high Middle Ages the notion of indiscriminate charity was becoming refined. High medieval canonical theory tried to make ethical differences: only the ›just‹, the ›honest‹ and the ›shameful‹ poor were to receive charity. In such a way the giving of alms came to be connected more closely with exhortations to make oneself useful– the notion of utilitas became more important, as expressed in the New Testament verse »who does not work shall not eat«. The categorization of persons according to their ability to work (if they were able to do so then begging was forbidden) or inability (whence begging was allowed) constituted a paradigmatic underpinning of the discourse pertaining to concepts of deserving and undeserving poor. In short, to that degree by which the value of work increased, the status of beggars decreased" (61).

Late Middle Ages:  Giacomo Todeschini, "Servitude et travail à la fin du Moyen Âge: La dévalorisation des salariés et les pauvres « peu méritants »," Annales:  Histoire, Sciences Sociales 70, no. 1 (January 2015): 81–89.

14th-15th centuries:  Mireia Comas-Via, "Widowhood and Economic Difficulties in Medieval Barcelona," Historical Reflections 43, no. 1 (Spring 2017): 93–103, gives the medieval distinction as pauperes verecundi and pobres de solemnitat or matricularii.

1300-1650:  Hadewijch Masure, "'Eerlycke huijsarmen' of 'ledichgangers'? Armenzorg en gemeenschapsvorming in Brussel, 1300-1640 [(Poor relief and community building in Brussels, 1300-1640)]," Stadsgeschiedenis 7, no. 1 (June 2012): 1–21.

1520 December:  Erasmus, In epistolam Iacobi canonicam paraphrasis at James 2:  "Therefore, the man who has by his flattery shown a preference for the undeserving rich man [(diuitem immerentem)] over the deserving poor man [(pauperi promere[n]ti)] is accountable for all the sins which are usually perpetrated against the love of neighbor, since he has broken this part of the law of love" (Collected works of Erasmus, ed. Robert D. Sider, vol. 44, Paraphrases on the epistles to Timothy, Titus, and Philemon; the epistles of Peter and Jude; the epistle of James; the epistles of John; the epistle to the Hebrews, trans. John J. Bateman (Toronto:  University of Toronto Press, 1993), 149; Tomus secundus continens Paraphrasim D. Erasmi Roterodami in omneis apostolicas epistolas (Basil, 1532), p. 336; cf. Opera omnia Desiderii Erasmi Roterodami VI.10 (Leiden:  Brill, 2014), p. ).  With thanks to Dr. Owen Ewald for his help with the abbreviation "promereti".

1525-1537:  Davis, Barbara Beckerman. “Reconstructing the Poor in Early Sixteenth-Century Toulouse.” French History 7, no. 3 (September 1993): 249–85.  "Most 16th-century poor relief programs institutionalized the practice of discriminating between "deserving" and "undeserving" poor. In addition, the people of Toulouse began to view charity as less a sacred duty and more a secular act. In response to short-term crises and deeper expectations raised after the Hundred Years' War, the city's population grew "more secular and less tolerant" of poverty and the poor. These feelings developed in a cultural climate of prosperity, order, and respectability."

1549, "Coverdale", translation of Erasmus' Paraphrasis of James 2:1-7:  "He yt hath..preferred the vndeseruing rich man before the deseruing pore man" (Oxford English dictionary).

1560-1650:  John McCallum, "Charity doesn’t begin at home: Ecclesiastical poor relief beyond the parish, 1560-1650," Journal of Scottish historical studies 32, no. 2 (November 2012): 107–26.

17th century:  Claire S. Schen, "Constructing the poor in early seventeenth-century London," Albion 32, no. 3 (June 2000): 450–63.   "Examines the flexibility in early-17th-century London of the categories of 'deserving' and 'undeserving' poor, which were constructed around demographic, military, religious, and social crises."

1650-1750:  David Hitchcock, Vagrancy in English culture and society, 1650-1750 (London & New York:  Bloomsbury, 2016).

1780-1850:   Samantha A. Shave, Pauper policies: Poor law practice in England, 1780–1850 (Manchester, Manchester University Press, 2017).  "The sharpening distinction that [Shave] perceives in select vestries after 1819 between the "deserving" and "undeserving" poor further supports her contention that the adopters were looking to reduce expenditure on poor relief" (2019 JIH review by Richard Smith).

[1840 (or earlier, given Alison, below)], Thomas Chalmers:  "mark the effect of the two discriminations.  With our system, when fully carried out, the practical result were a full measure of relief for the deserving, with a leaving out of the undeserving poor.  With their system when fully carried out, the practical result is that the undeserving, the men of hardihood, who can brook the indignities of a work-house and the violence there done to the feelings of relationship, are all taken in—while the deserving are revolted and scared away"(Thomas Chalmers, On the sufficiency of the parochial system, without a poor rate, for the right management of the poor (Glasgow:  Wm. Collins, 1841 [ ]), 161).

1840, William Pulteney Alison:  "The practical object which Mr Bosanquet seems to have in view, so far as his desponding views allow him to anticipate any improvement, is nearly the same as that of Dr Chalmers (except that he professes no intention of 'leaving out' a class of undeserving poor, maintaining, on the contrary, as I do, and as is almost universally done in England, that all misery is entitled to consolation and relief)—viz. to impress on the minds of the higher ranks of society so strong a sense of the Christian duty which the state of the poor imposes on them, as to induce them to make a liberal and discriminating voluntary provision for them ‘on the plan of district visiting,’ in all parts of the country" (William Pulteney Alison, Observations on the management of the poor in Scotland:  and its effects on the health of the great towns, 2nd ed. (Edinburgh:  William Blackwood & Sons, 1840), 40; Dr. Chalmers (above) is quoted on p. 5 and elsewhere).

1878 February 1:  "The frontier provinces of France and Germany, in the later Middle Ages, seem to have suffered as much from tramps as the thinly peopled rural districts in the United States do at the present day.  In 1391 the town of Bâle made an alliance with the Bishop of Strasburg and with other lords against the troops of marauding beggars who devastated the lands on the Rhine.  The league seems to have been so far successful that private persons could be trusted, for the future, to guard their own property, if only they were able to discriminate between the 'deserving' and the undeserving poor.  For the guidance of the benevolent, a writer who calls himself expertus in trufis, 'skilled in knaveries,' produced at the end of the fifteenth century the 'Liber Vagatorum,' or 'Book of Tramps.'  The author of this manual is supposed by some authorities to have been Sebastian Brant. . . .  Others will have it that he was one Murner" ("A book of tramps," The Pall Mall budget, being a weekly collection of articles printed in the Pall Mall gazette from day to day:  with a summary of news 19, [no. 18] (Friday, 1 February 1878), p. 11, col. 2).

1891, Henry Sidgwick:  "the distinctive principle of the English system is that Government is not to discriminate between the deserving and the undeserving poor, but to secure to all who are destitute a minimum of subsistence under conditions deterrent but not painful:  and this principle would be rejected as too harsh by many who now accept it, were it not for the assumption that private almsgivers will be ready to undertake the task of discrimination which Government declines, and to accord more generous and tender treatment to those who have fallen into distress through undeserved calamities" (Henry Sidgwick, The elements of politics (London:  Macmillan & Co., 1891), 202).  A debate over the justice of the distinction seems to have raged during the Victorian period, so there is much more where this comes from.
Indeed, according to the OED, the roots of it might be traced back, in English at least, to 1549 (above), if not before.  For but one example of the opposite opinion, see 1907 (below).

1900-1930:  David T. Beito, "Mutual aid, state welfare, and organized charity: Fraternal societies and the ‘deserving’ and ‘undeserving’ poor, 1900-1930," Journal of policy history 5, no. 4 (October 1993): 419–34.  "Examines two [American?] working-class aid societies that provided welfare assistance to members."

1907 October (W. M. Lightbody):  "One must, of course, admit the full force of the objection that, although the present system does not reform the neglectful parent, the proposed system would tend to demoralize those who at present do their duty.  That such would be the effect under our existing Poor Law administration admits of little doubt; for little or no attempt is made to discriminate between the deserving and the undeserving poor, or between different causes of poverty" (W. M. Lightbody, “The State and the children,” Economic review 17, no. 4 (October 1907):  439).

c. 2001, supposedly "Dorothy Day" (pseudo-Dorothy Day):  "The gospel takes away our right forever, to discriminate between the deserving and the undeserving poor."  Though Dorothy Day (1897-1980) does indeed seem to have been of this opinion, and invokes the distinction more than once, I have yet to track this very sentence to any of her known works or sayings, not even in the Catholic Worker-sponsored Dorothy Day Library on the Web.  (Update:  Some have cited the issue of The Catholic worker dated May of 1940, but it was not present in any of the four articles she wrote for that issue that had been uploaded to that "complete set" of her contributions by 6 August 2020.)  Nor was I able (in mid-July of 2015) to get Google to turn it up in a search limited to the years before 2001. What is more, Day specialists and authors James Allaire (Webmaster, Dorothy Day Library on the Web), Robert Ellsberg (Publisher, Orbis Books), Jim Forest (like some of the others a Day biographer), and Phillip M. Runkel (Archivist, Dorothy Day-Catholic Worker Collection, Special Collections and University Libraries, Raynor Memorial Libraries, Marquette University) all concur in suspecting it (which is to say the very sentence) of inauthenticity (correspondence with Steve Perisho, week of 13 July 2015).  My guess is that it derives from (at best) some second party's encapsulating summary or reformulation of her position (itself somewhat unoriginal (Sidgwick and others, above)).

     Needless to say, people have obviously been taking sides around this distinction for a very long time, such that what I have provided above (whether in the way of quotations or of scholarship) is but a very small fraction of what one easily could.  (Many of the promising hits on "undeserving poor" in TX All Text AND NOT Review in the Atla Religion Database, Historical Abstracts, and America:  History and Life dated later than 2005 were not examined, nor were any dated earlier.)  Some of the adjectival alternatives I've encountered so far:  deviant, meritorious, pauvres peu méritants, sturdy, (un)worth*, wandering, etc.

"ask grace, not doctrine; desire, not intellect; the groaning of prayer and not studious reading"

"seek the answer in God’s grace, not in doctrine; in the longing of the will, not in the understanding; in the sighs of prayer, not in research; seek the bridegroom not the teacher; God and not man; darkness not daylight; and look not to the light but rather to the raging fire that carries the soul to God with intense fervor and glowing love [(interroga gratiam, non doctrinam; desiderium, non intellectum; gemitum orationis, non studium lectionis; sponsum, non magistrum; Deum, non hominem, caliginem, non claritatem; non lucem, sed ignem totaliter inflammantem et in Deum excessivis unctionibus et ardentissimis affectionibus transferentem)]. The fire is God, and the furnace is in Jerusalem, fired by Christ in the ardor of his loving passion. Only he understood this who said: My soul chose hanging and my bones death. Anyone who cherishes this kind of death can see God, for it is certainly true that: No man can look upon me and live."

     St. Bonaventure, Itinerarium mentis in Deum 7.6, as translated in the Liturgy of the hours, Office of readings for the Feast of St. Bonaventure.  Latin from p. 313 of vol. 5 of the Quaracchi edition as reproduced in Itinerarium mentis in Deum, trans. Zachary Hayes, Works of St. Bonaventure (Saint Bonaventure, NY:  Franciscan Institute Publications, 2002), 138.  (The translation in the heading, however, is taken from the one by Hayes.)

     Yet this comes, of course, at the end of a long and rigorous itinerarium.  "For Saint Bonaventure is an intellectual, although not an intellectualist; his vocation is that of a theologian who craves for understanding.  Intellectual activity is as necessary for him [(as distinguished from his master, Saint Francis of Assisi)] as his daily bread" (Philotheus Boehner, OFM, in the "Notes and commentary" (p. 220 of the Franciscan Institute edition given above)).