1 John 3:3 - Joseph Benson’s Commentary on the Old and New Testaments

And every man that hath this hope in him An expectation of seeing Christ as he is, built on a solid foundation, namely, the foundation of being a child and heir of God; purifieth himself By applying to, and confiding in, the purifying blood of Christ, with a penitent, believing heart; by earnestly praying for and receiving the purifying Spirit of God; by obeying the purifying word, (1 Peter 1:22,) and by exercising purifying faith in the truths and promises of the gospel, Acts 15:9: even as he is pure The person who is inspired with this well-grounded hope, will keep before his eyes the pure and holy character of Christ, as the mark to which he is to press, that he may be prepared to receive the prize of his high calling of God in Christ Jesus, (Philippians 3:14,) it being God's will and pleasure that believers should be conformed to the image of his Son, in order to their having the high honour and great happiness of dwelling with him, Romans 8:29; and that they should not expect to enjoy the privilege of sitting down at the marriage-feast, unless they had previously put on the wedding-garment. Mark this, reader: and give up all hope of being admitted into heaven hereafter, without a conformity to Christ in holiness here.