Thematic Bible: Who became vain

This I say therefore, and testify in the Lord, that ye should no longer walk as the rest of the nations walk in the vanity of their mind, being darkened in understanding, estranged from the life of God by reason of the ignorance which is in them, by reason of the hardness of their hearts, who having cast off all feeling, have given themselves up to lasciviousness, to work all uncleanness with greedy unsatisfied lust.

For there is revealed wrath of God from heaven upon all impiety, and unrighteousness of men holding the truth in unrighteousness. Because what is known of God is manifest among them, for God has manifested it to them, for from the world's creation the invisible things of him are perceived, being apprehended by the mind through the things that are made, both his eternal power and divinity, so as to render them inexcusable. read more.
Because, knowing God, they glorified him not as God, neither were thankful; but fell into folly in their thoughts, and their heart without understanding was darkened: professing themselves to be wise, they became fools, and changed the glory of the incorruptible God into the likeness of an image of corruptible man and of birds and quadrupeds and reptiles.