I would not use poezie (sg.) / poezii (pl.) to describe the lyrics of a Christian song. Lyrics should be translated as "versuri".
The Christian songs and Christian poetry are not wide spread as a genre in the Romanian culture the same way they are encountered in USA, for example.
Imnuri religioase, psalmi and cântări are the terms we'd use more often (religious hymns, psalms and chants).
I was thinking that perhaps Christian poetry might be better served in translation as Poeme (religioase) creștine. This way we preserve the religious and Christian character of the Christian poems and the genre (poetry).