This week I was looking at P.Bodmer XIV-XV (P75, Luke and John) and came across a very interesting phenomenon in the text of John 3:8 in P.Bodmer XV. John 3:8 reads: "The wind (πνεῦμα) blows (πνεῖ) where it wishes, and you hear its sound, but do not know from where it comes, and to where it goes: so is every one that is born of the Spirit." The scribe of P.Bodmer XIV-XV writes both the noun "wind" and the verb "blows" as nomina sacra:
It was common for words that were used profanely (i.e., non-religious, as opposed to sacral) to be written as nomina sacra, especially when those words were also used as nomina sacra, like the word "wind" in this case. To cite another example, in Mark 1:26 Codex Sinaiticus writes "unclean spirit" (τὸ πνεῦμα τὸ ἀκάθαρτον) as a nomen sacrum even when the referent is a demon! In the case of P.Bodmer XV above, the scribe likewise gives overlining to the verb "to blow," which is linguistically related to the noun πνεῦμα. This is very interesting. In the context of this verse, wind is a metaphor for the Spirit, and this is probably the reason the scribe marked the verb with overlining. I know of no other instance where this verb is marked with overlining and treated as a nomen sacrum.