Why do we have "Christians" that don't act like children of God? Because they are in the flesh and cannot see who God has made them in Christ, in the Spirit. "two cannot walk together unless they agree"...those who have been taught the Holy Spirit is following them around, finding their sins...are not in a true relationship with the Holy Spirit and are not able to draw from the Spirit the power and life to overcome the weakness of their flesh. Its those who know the Holy Spirit is always there to justify and give grace that overcome the flesh and the lust in this world...
Basically a half-saved sinner will act like a half-saved sinner...
A righteous child of God will act like a righteous child of God!
Romans 8:5-8, "For those who live according to the flesh, set their minds on the things of the flesh; but those who live according to the Spirit, set their minds on the things of the Spirit. For to be carnally minded is death; but to be spiritually minded is life and peace. Because the carnal mind is enmity against; (bitterly opposed to), Yahweh; for it his not subject to the Law of Yahweh, nor indeed can be. So then, those who are of the flesh cannot please Yahweh."
Isayah 5:20, "Woe to those who call evil righteous, and righteous evil; who put darkness for light, and light for darkness; who put bitter for sweet, and sweet for bitter!"
Ezekiyl 36:26-27, "A new heart; mind, will I also give you, and a new spirit will I put within you; and I will take away the heart of stone out of your flesh, and will give you a heart of flesh. And I will put my Spirit in you and move you to follow my decrees and be careful to keep My Laws."