In this sentence, which in Greek goes through verse 30, the emphatic element is I. Even though the phrase rendered after I leave originally meant something like “after my arrival,” scholars understand the meaning here as after I leave.

Fierce wolves is a reference to the false teachers who will come in and not spare the flock (that is, the church). The reference in this verse is to outsiders who will come and try to indoctrinate the church with their false teaching. The translation of fierce wolves and flock involves serious problems in a number of languages. In the first place, wolves may not even be known in the region, and therefore the closest equivalent may be “fierce wild dogs” or “fierce wild hyenas.” In still other languages a more general expression must be employed, namely, “fierce animals” or “animals that kill and destroy.” However, even if an appropriate term for fierce wolves may be found, it is questionable whether one can always employ this type of metaphor. It is too easy in some languages for such an expression to be understood literally. Therefore, in some languages one may employ “men will come among you and act like fierce animals.”

Will not spare the flock may be equivalent to “will not leave the flock uninjured.” However, as in verse 28, it may be necessary to specify that the flock here applies to “the believers” or “the congregation.”

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 .