It is possible that the origins of the second-mode tracts are as old as the fourth century, when the Lenten liturgical cycle from Quadragesima to Easter came into being. The tracts have frequently been singled out as a particularly ancient genre: the great length of Deus deus meus and Qui habitat in particular has often been seen as a remnant of the fourth-century practice of singing an entire psalm in directum (straight through, without repeats or refrains). In the early Church, the music heard between the readings of the Mass consisted of psalms sung by a solo-ist or ‘lector’, with congregational responds. There was no fixed repertory. Instead, psalms were chosen and melodies used, or improvised, on an ad hoc basis. At some point in the early Middle Ages, there was a repertorial and institutional shift to ‘schola’ chant, whereby a fixed repertory of proper texts and melodies (graduals, alleluias, tracts etc.) was sung in the Mass in an annual cycle by clerics or monastics whose primary duty was singing. Pinpointing the timing and nature of this shift and of the emergence of the Mass Proper repertory would be critical to establishing the likely dating of the second-mode tracts in anything approximating their current textual, musical and generic state, but this continues to exercise scholars.

In The Advent Project, McKinnon argued that the Mass Proper repertory was composed (or at least compiled) by the papal schola cantorum of secular canons based at St John in the Lateran, Rome, in a conscious project in the later-seventh century. This hypothesis has been challenged by several reviewers, perhaps most notably by Pfisterer, who argues persuasively that the repertory evolved gradually over several centuries, and was substantially complete by the early-seventh century. Pfisterer's dating of some chant texts to as early as the fifth century is less convincing, however. Securely dated versions of biblical texts do not necessarily map directly onto securely datable versions of chant texts since older versions of biblical texts are not necessarily put aside as soon as new ones are made. Instead, chant compilers may have drawn on texts old and new, including pre-existing liturgical texts, and for some chants they certainly paraphrased existing biblical texts in creating ‘libretti’ for liturgical chants.