Saint-Saëns: Christmas Oratorio, Op. 12: II. Recit et chœur

I'd forgotten about this, but one of my goals for 2020 was to post some old notes on Saint-Saëns' Christmas Oratorio.

In the second movement, when the soprano sings "Et hoc vobis signum" ("And this to you a sign" - the first part of Luke 2:12), the musical setting of "vobis signum" forms a cross:

I feel that this has significance, but I can't come up with a good explanation for it.

The chœur section of the second movement has the text "Gloria in altissimis Deo, et in terra pax..." ("Glory to God in the highest, and on earth peace..." - Luke 2:14).  "Gloria in altissimis Deo" is first sung by the sopranos and the altos, the higher voices, and "Et in terra pax" is first sung by the tenors and the basses, the lower voices:

Distributing those parts of the text among those particular voices results in an audible representation of the highness of heaven and the lowness of earth.

Furthermore, the "altissimis" ("highest") is set across a series of rising notes, indicating that height: