Grishka, as I understand it, the notes refer to this version which is pitched to children just entering schooling, which before the Acadian expulsion was exclusively in French Catholic schools and taught by members of the church. Very simple explanations are necessary for a small child, first attending school and getting his first Catholic instruction.
The French language explanation with reference to "chansons de geste du moyen âge" in a preceding note in the booklet with the songs is not, I think, wholly justified, but I don't have the book in which Marius Barbeau included the song and which should have his notes on collection.