'Flesh' in the Bible

For all that is in the world, the lust of the flesh, the lust of the eyes, and the pride of life, isn't the Father's, but is the world's.

By this you know the Spirit of God: every spirit who confesses that Jesus Christ has come in the flesh is of God,

and every spirit who doesn't confess that Jesus Christ has come in the flesh is not of God, and this is the spirit of the Antichrist, of whom you have heard that it comes. Now it is in the world already.