in purpose and performance

"O God, strength of those who hope in you, graciously hear our pleas, and, since without you mortal frailty can do nothing, grant us always the help of your grace, that in following your commands we may please you by our resolve and our deeds.  Through."

"Deus, in te sperantium fortitudo, invocationibus nostris adesto propitius, et, quia sine te nihil potest mortalis infirmitas, gratiae tuae praesta semper auxilium, ut, in exsequendis mandatis tuis, et voluntate tibi et actione placeamus.  Per."

     Collect, Eleventh Sunday in Ordinary Time, Missale Romanum.  =Corpus orationum no. 1245:

"Deus, in te sperantium fortitudo, adesto propitius invocationibus nostris et, quia sine te nihil potest mortalis infirmitas, praesta auxilium gratiae tuae, ut, in exsequendis mandatis tuis et voluntate tibi et actione placeamus.  Per."

This (which lacks the semper added to it after Vatican II) is present in the mid 8th century Old Gelasian (Rome, Vatic. Reg. Lat. 316, 88r; Mohlberg, Eizenhöfer, & Sifrin, eds. Liber sacramentorum Romanae Ecclesiae ordinis anni circuli (Rome, 1965) no. 566; Wilson, ed. (Oxford, 1894) no. 587), as well as a couple of other 8th-century sacramentaries (Gellon., Rhen.); and, although Corpus orationum doesn't mention this, in the Gregorian (Hadrianum), which was copied from an earlier Roman original in 811-812 (Deshusses, Le sacramentaire Grégorien (Fribourg, 1992) no. 1129 (vol. 1, 3rd. ed., p. 390; also nos. 595, 1964, etc.).

1979:  Book of common prayer, Sixth Sunday after the Epiphany, Contemporary:  "O God, the strength of all those who put their trust in you:  Mercifully accept our prayers; and because in our weakness we can do nothing good without you, give us the help of your grace, that in keeping your commandments we may please you both in will and deed; through."

1979:  Book of common prayer, Sixth Sunday after the Epiphany, Traditional:  "O God, the strength of all those who put their trust in thee:  Mercifully accept our prayers; and because, through the weakness of our mortal nature, we can do no good thing without thee, grant us the help of thy grace, that in keeping thy commandments we may please thee both in will and deed; through."

1928:  The book of common prayer, First Sunday after Trinity:  "O God, the strength of all those who put their trust in thee; Mercifully accept our prayers; and because, through the weakness of our mortal nature, we can do no good thing without thee, grant us the help of thy grace, that in keeping thy commandments we may please thee, both in will and deed; through."

1892:

1662:  The book of common-prayer, First Sunday after Trinity (as ed. Brian Cummings (Oxford, 2011)):  "O God, the strength of all them that put their trust in thee, mercifully accept our prayers; and because through the weakness of our mortal nature we can do no good thing without thee, grant us the help of thy grace, that in keeping of thy commandments we may please thee, both in will and deed, through."

1549:  The booke of the common prayer, First Sunday after Trinity (Everyman First and second Prayer books of 1910):  "God, the strength of all theym that trust in thee, mercifully accept our prayers; and because the weakenes of oure mortall nature can do no good thyng without thee, graunt us the helpe of thy grace, that in kepyng of thy commaundementes we may please thee, both in will and dede; through."