From his sermon, “The Holy Spirit in the Covenant,” preached on a Lord’s Day morning, 1856

What a vain pretense it is to profess to honor God by a doctrine that makes salvation depend on the will of man! If it were true, you might say to God, “We thank thee, O Lord, for what thou hast done; thou hast given us a great many things, and we offer thee thy meed* of praise, which is justly due to thy name; but we think we deserve more, for the deciding point was in our free will.” Beloved, do not any of you swerve from the free grace of God, for the babblings about man’s free agency are neither more nor less than lies, right contrary to the truth of Christ, and the teachings of the Spirit.

How certain, then, is the salvation of every elect soul! It does not depend on the will of man; he is “made willing” in the day of God’s power. He shall be called at the set time, and his heart shall be effectually changed, that he may become a trophy of the Redeemer’s power. That he was unwilling before, is no hindrance; for God giveth him the will, so that he is then of a willing mind. Thus, every heir of heaven must be saved, because the Spirit is put within him, and thereby his disposition and affections are molded according to the will of God.

*Meed = reward, fitting return, recompense

More of Spurgeon on God’s Sovereignty

Brethren, if God does not rule everywhere, then something rules where he does not, and so he is not omnipresently supreme. If God does not have his will, someone else does, and so far that someone is a rival to God. I never deny the free agency of man, or diminish his responsibility, but I dare never invest the free will of man with omnipotence, for this were to make man into a sort of God, an idolatry to be loathed. Moreover, admit chance anywhere, and you have admitted chance everywhere, for all events are related and act on one another. One cog of the wheel of providence disarranged or left to Satan, or man’s absolute freedom apart from God, would spoil the whole machinery. I dare not believe even sin itself to be exempted from the control of providence, or from the overruling dominion of the Judge of all the earth. Without providence we were unhappy beings, without the universality of the divine power providence would be imperfect, and in some points we might be left unprotected and exposed to those evils which are, by this theory, supposed to be beyond divine control. Happy are we that it is true, “the Lord doeth as he wills in the army of heaven, and among the inhabitants of the earth.”

Spurgeon, Charles, Spurgeon’s Sermons Volume 16, (Albany, OR: Ages Software) 1998.