Albert Barnes Commentary Acts 21:27

"And when the seven days were almost completed, the Jews from Asia, when they saw him in the temple, stirred up all the multitude and laid hands on him," — Acts 21:27 (ASV)

And when the seven days were almost ended. Greek: As the seven days were about to be fulfilled. (The Greek is emellon sunteleisyai). These were the seven days required to complete the observance of the vow (Acts 21:26). Perhaps the entire observance in this instance was intended to last only seven days, since the duration of such a vow was voluntary.

The translation, "were almost ended," is not entirely accurate. The Greek implies only that the period of the seven days was about to be accomplished, not that it was near their end when he was seized.

By comparing the following passages—Acts 21:18, 26; 22:30; 23:12, 32; and 24:1, 11—it appears that the time of his seizure must have been near the beginning of those days (Doddridge).

The Jews who were of Asia. These were Jews who resided in Asia Minor but had come to Jerusalem for worship (see Barnes on Acts 2:1 and following).