Nunc scio vere, quia misit Dominus Angelum suum: et eripuit me de manu Herodis, et de omni expectatione plebis Judaeorum.
“Now I know for certain that the Lord has sent his angel. And he relieved me from the hand of Herod and from all the expectation of the crowd of the Jews.” (Acts 12:11)
The Solemnity of Peter and Paul has two Mass propers: one for the eve, and one for the day itself. Surprisingly the chants of both Masses almost completely focus on Peter (Paul only gets the second readings in both Masses).
In Nunc scio I find – as in many other chants – a nice play with the melodic directions upwards and downwards: Misit Dominus Angelum suum (“the Lord has sent his angel”) moves from the top downwards as if there came something from heaven down to earth. And eripuit me (he relieved me) lets me hear how Peter is lifted up by a power that is not his own.