The passive expression had been instructed in may be rendered as “he had learned thoroughly about.”

The idiom “boiling over in spirit” appears in the Good News Translation as with great enthusiasm. Most translators take “spirit” to mean Apollos’ own spirit, with the meaning with great enthusiasm or “filled with enthusiasm.” However, some see here a reference to the Holy Spirit. In this type of context, enthusiasm may be rendered as “great earnestness,” “he meant strongly what he was saying,” or even “he spoke as one who knew that what he was talking about was very important.”

On the baptism of John see 1.22.

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 .