Thematic Bible: Who purifies their soul

Behold how great love the Father has bestowed on us, that we should be called children of God! For this reason, the world does not know us, because it did not know him. Beloved, now we are the children of God; but it does not yet appear what we shall be. However, we know that when he shall appear, we shall be like him-that we shall see him as he is. And every one who has this hope in him purifies himself, even as He is pure.

but with the precious blood of Christ, as of a lamb without blemish, and without spot; predetermined, indeed, before the foundation of the world, but manifested in these last times for you; who through him, believe in God, who raised him up from the dead, and gave him glory, that your faith and hope might be in God. read more.
Wherefore, having purified your souls by obeying the truth, through the Spirit, to unfeigned brotherly love, love one another, from a pure heart, fervently: having been regenerated, not of corruptible seed, but of incorruptible, through the word of the living God, which remains.