A.T. Robertson Commentary Acts 21:22

"What is it therefore? They will certainly hear that thou art come." — Acts 21:22 (ASV)

What is it therefore? (Τ ουν εστιν?). See this form of question by Paul (1 Corinthians 14:15,26). What is to be done about it? Clearly James and the elders do not believe these misrepresentations of Paul's teaching, but many do.

They will certainly hear (παντως ακουσοντα). Παντως is old adverb, by all means, altogether, wholly, certainly as here and 28:4; Luke 4:23; 1 Corinthians 9:10. This future middle of ακουω is the usual form instead of ακουσω. There was no way to conceal Paul's arrival nor was it wise to do so. B C and several cursives omit δε πληθος συνελθειν (The multitude must needs come together).