But Peter rehearsed - Greek: Peter beginning, explained it to them in order; that is, he began with the vision which he saw, and gave a narrative of the various events in order, as they actually occurred. A simple and unvarnished statement of facts is usually the best way of disarming prejudice and silencing opposition. Opposition most commonly arises from prejudice, or from false and exaggerated statements, and such opposition can be best removed, not by angry contention, but by an unvarnished relation of facts. In most cases prejudice will thus be disarmed, and opposition will die away, as was the case in regard to the admission of the Gentiles to the church.
And expounded it - Explained it; stated it as it actually occurred.
In order - One event after another, as they happened. He thus showed that his own mind had been as much biased as theirs, and stated in what manner his prejudices had been removed. It often happens that those who become most zealous and devoted in any new measures for the advancement of religion were as much opposed to them at first as others. They are led from one circumstance to another, until their prejudices die away, and the providence and Spirit of God indicate clearly their duty.