'Heard' in the Bible

For you have heard of my former way of life in Judaism, how I was savagely persecuting the church of God and trying to destroy it.

The only thing I want to learn from you is this: Did you receive the Spirit by doing the works of the law or by believing what you heard?

Does God then give you the Spirit and work miracles among you by your doing the works of the law or by your believing what you heard?