Adam Clarke on Galatians 1:13

Ye have heard of my conversation - Την εμην αναστροφην· My manner of life; the mode in which I conducted myself.

Beyond measure I persecuted the Church - For proofs of this the reader is referred to Act 9:1-2 (note); Act 22:4 (note), and the notes there. The apostle tells them that they had heard this, because, being Jews, they were acquainted with what had taken place in Judea, relative to these important transactions.