And I will make an everlasting covenant with them, that I will not turn away from them, to do them good… – Jeremiah 32:40

The first covenant was conditioned upon the obedience of men. If they kept the law, God would bless them; but they failed through disobedience and inherited the curse. The divine sovereignty determined to deal with men, not according to merit, but according to mercy; not according to the personal character of men, but according to the personal character of God; not according to what men might do, but according to what the Lord Jesus would perform. Sovereign grace declares that He will have mercy upon whom He will have mercy and will have compassion on whom He will have compassion. This basis of sovereignty cannot be shaken. The covenant which saves men according to God’s will and good pleasure, is founded upon a rock; for God’s free grace is always the same, and God’s sovereignty is linked to immutability, even as it is written, “I am the Lord, I change not; therefore ye sons of Jacob are not consumed.” The slightest touch of merit puts perishable material into the covenant; but if it be of pure grace, then the covenant is everlasting.

It is necessary that a man, to be forgiven, should repent; but then the Lord Jesus is exalted on high to give repentance and remission of sins. It is necessary that a man, in order to be saved, should have faith in the Lord Jesus Christ; but faith is of the operation of God, and the Holy Ghost worketh in us this fruit of the Spirit. It is needful, before we enter heaven, that we should be holy; but the Lord sanctifies us through the Word, and worketh in us to will and to do of His own good pleasure. All that is required is also supplied. If there be, anywhere in the Word of God, any act or grace mentioned as though it were a condition of salvation, it is in another Scripture described as a covenant gift which will be bestowed upon the heirs of salvation by Christ Jesus. So that the condition, which might seem to put the covenant in danger, is so surely provided for, that thence ariseth no flaw or fracture. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/2108.cfm