Aware of his situation translates a single verb in the Greek (literally, “when he realized”) that has no object, and so the object must be supplied from the context such as the New English Bible “when he realized how things stood” and the Jerusalem Bible “as soon as he realized this.” One may render aware of his situation by such expressions as “now knowing what had happened” or “seeing what had really happened.”

It is interesting that Mary is identified by the addition of her son’s name John Mark, though it was more natural to identify a person by the father than by his son. This is the first mention in Acts of John Mark. It is typical of Luke’s writing to introduce a person such as John Mark by this kind of brief reference, particularly when he is going to be mentioned in the text later (12.25; 13.5, 13; 15.37-39).

Were praying may require in many languages some grammatical object, for example, “were praying to God for Peter.”

Quoted with permission from Newman, Barclay M. and Nida, Eugene A. A Handbook on The Acts of the Apostles. (UBS Handbook Series). New York: UBS, 1972. For this and other handbooks for translators see here .