The following quote by Martin Luther, from The Bondage of the Will, is one of the main points of the Reformation, the biblical truth that the salvation of sinners belongs completely and wholly to the Lord:
“A man cannot be thoroughly humbled till he realizes that his salvation is utterly beyond his own powers, counsels, efforts, will and works, and depends absolutely on the will, counsel, pleasure and work of Another – God alone. As long as he is persuaded that he can make even the smallest contribution to his salvation, he remains self-confident and does not utterly despair of himself, and so is not humbled before God; but plans out for himself (or at least hopes and longs for) a position, an occasion, a work, which shall bring him final salvation. But he who is out of doubt that his destiny depends entirely on the will of God despairs of himself entirely, chooses nothing for himself, but waits for God to work in him; and such a man is very near to grace for his salvation.”
“…So these truths are published for the sake of the elect, that they may be humbled and brought down to nothing, and so saved. The rest of men resist this humiliation; indeed, they condemn the teaching of self-despair; they want a little something left they can do for themselves. Secretly they continue proud, and enemies of the grace of God. This, I repeat, is one reason – that those who fear God might in humility comprehend, claim and receive his gracious promise.” Martin Luther, Bondage of the Will, II.vii.
Covenant Presbyterian Church (OPC)