A.T. Robertson Commentary Acts 10:36

"The word which he sent unto the children of Israel, preaching good tidings of peace by Jesus Christ (He is Lord of all.) --" — Acts 10:36 (ASV)

The word which he sent (τον λογον ον απεστειλεν). Many ancient MSS. (so Westcott and Hort) read merely τον λογον απεστειλεν (he sent the word). This reading avoids the anacoluthon and inverse attraction of λογον to the case of the relative ον (which).

Preaching good tidings of peace through Jesus Christ (ευαγγελιζομενος ειρηνην δια Ιησου Χριστου). Gospelizing peace through Jesus Christ. There is no other way to have real peace between individuals and God, between races and nations, than by Jesus Christ. Almost this very language occurs in Eph 2:17 where Paul states that Jesus on the cross "preached (gospelized) peace to you who are afar off and peace to you who are near." Peter here sees what Paul will see later with great clearness.

He is Lord of all (ουτος εστιν παντων κυριος). A triumphant parenthesis that Peter throws in as the reason for his new truth. Jesus Christ is Lord of all, both Jews and Gentiles.