John Calvin Reformed @genevareformer

1. For this cause. Paul’s imprisonment, which ought to have been held as a confirmation of his apostleship, was undoubtedly presented by his adversaries in an opposite light. He therefore points out to the Ephesians that his chains served to prove and to declare his calling; and that the only reason why he had been imprisoned was, that he had preached the gospel to the Gentiles.

Matthew Henry Presbyterian @wholebiblehenry

Here we have the account which Paul gives the Ephesians concerning himself, as he was appointed by God the apostle of the Gentiles. I. We may observe that he acquaints them with the tribulations and sufferings which he endured in the discharge of that office, Eph 3:1. The first clause refers to the preceding chapter, and may be understood either of these two ways: - 1.

Commenting on Ephesians 3:1-13

John Gill Reformed Baptist @doctorgill

For this cause I Paul, the prisoner of Jesus Christ,.... Not actively, whom Christ had apprehended by his grace, and made a prisoner of hope; but passively, who was made a prisoner for Christ, on account of preaching Christ, and his Gospel: he was not a prisoner for any capital crime, as theft, murder, &c.