|Quóniam mihi adhæsit, liberábo eum||Since he has clung to me, I shall free him.|
Quoniam = because, since, seeing that.
mihi = to me.
adhæsit = he has clung to, from adhaerere, or adhaerescere. Perfect tense. The perfect tense is formed using the third principle part as found in the dictionary. Here, with both verbs, it is adhæsi.
liberabo eum = I shall free him.