In the entry
“crisma” (Engl. chrism) we get an explanation of how the abbreviation
“Christus” came into being. This is exciting, because it’s very unusual for the dictionary to provide information on the etymology and use of abbreviations.
crisma grece unxio latine .t. kresem inde venit grece
cristus xpc hoc est Cristus quod scribitur grece in breviatura que tribus grecis literis que sunt c r s et quia sunt similes nostris x p c ideo ignari dicunt Cristus x p c esse scriptum literis latinis cum sint grece litere scilicet cappa cappa res sima inde Cristianus -a -um et ‘Cristi’anitas et Cristianismus quasi Cristianorum mos
Translation: “[…] xpc that is Christus which is spelled in Greek as an abbreviation with three Greek letters which are c r s. And because they are similar to our [letters] x p c, those who are unaware of this think that Christus, [abbreviated as] xpc, is spelled in Latin letters, whereas they are [actually] the Greek letters kappa rho sigma […]”
It seems as if neither of the two scribes knew that an orthographic explanation for the xpc-abbreviation would follow when they started writing the entry: Ms956 spelled the word
“cristus” in full before crossing it out and replacing it with the xpc-abbreviation, whereas Ms720 did use an abbreviation, but a different one: the x for Christus followed by the common abbreviation for the ending -us.
Furthermore, the orthographic explanation obviously didn’t influence the scribes’ own spelling habits much, because in the following entries Ms720 continues to use the x+us abbreviation instead of xpc, and Ms956 usually spells any form of Christus in full and doesn’t use abbreviations at all.