Albert Barnes Commentary Acts 15:33

"And after they had spent some time [there], they were dismissed in peace from the brethren unto those that had sent them forth." — Acts 15:33 (ASV)

A space. For some time.

They were let go in peace. This expression implies that they departed with the affectionate regard of the Christians to whom they had ministered, and with their highest wishes for their prosperity (1 Corinthians 16:11; 2 John 1:10). Silas, however, it seems, chose to remain.

Unto the apostles. This refers to the apostles at Jerusalem. Many manuscripts, however, instead of "unto the apostles," read, "unto those who had sent them." The sense is not materially different.

It is also noted that tarried can mean abode; a space signifies for some time; and let go can be rendered as dismissed. For the term peace, compare its usage in 1 Corinthians 16:11 and 2 John 1:10.