18 A good tree cannot bear bad fruit, and a bad tree cannot bear good fruit.
Matthew 7:18 Cross References - VIN
Galatians 5:17
17 For the flesh craves what is contrary to the Spirit, and the Spirit what is contrary to the flesh. They are opposed to one another, so that you do not do what you want.
1 John 3:9-10
9 Anyone born of God refuses to practice sin, because God’s seed abides in him; he cannot go on sinning, because he has been born of God.
10 In this the children of God are manifest, and the children of the devil; for every one who does not work righteousness is not a child of God, nor is he who does not love his brother.