The embolism (ἐμβολισμός) or Libera nos pre- and post-Vatican II

Extraordinary Form (1962)

Novus Ordo

Deliver us, we beseech Thee, O Lord, from all evils, past, present and to come; and by the intercession of the blessed and glorious ever Virgin Mary, Mother of God, and of the holy Apostles, Peter and Paul and of Andrew, and of all the Saints, mercifully grant peace in our days, that through the assistance of Thy mercy we may be always free from sin, and secure from all disturbance.  Through. Libera nos, quaesumus Domine, ab omnibus malis, praeteritis, praesentibus, et futuris:  et intercedente beata, et gloriosa semper Virgine Dei Genitrice Maria, cum beatis Apostolis tuis Petro et Paulo, atque Andrea, et omnibus Sanctis, da propitius pacem in diebus nostris:  ut ope misericordiae tuae adjuti, et a peccato simus semper liberi, et ab omni perturbatione securi.  Per.

Deliver us, Lord, we pray, from every evil, graciously grant peace in our days, that, by the help of your mercy, we may be always free from sin and safe from all distress, as we await the blessed hope and the coming of our Saviour, Jesus Christ. Libera nos, quaesumus Domine, ab omnibus malis, da propitius pacem in diebus nostris, ut, ope misericordiae tuae adiuti, et a peccato simus semper liberi et ab omni perturbatione secure:  exspectantes beatam spem et adventum Salvatoris nostri Iesu Christi.

     It's surely more complicated than this historically (ODCC4 cites only "Jungmann (1958 edn), 2: 352–63; Eng. tr., 2: 284–93"), but this one comparison, at least, is rather striking.