For whatsoever is born of God overcometh the world: and this is the victory that overcometh the world, even our faith. – 1 John 5:4

The Lord God of Israel will never stain His glory, wherefore be ye confident that He who brought you out of Egypt will bring you into Canaan. “Ah” murmurs one, “I don’t believe that!” Then I am sorry for you; for “according to your faith be it unto you.” “I believe,” says one, “that men fall away and perish.” It will be an evil thing for you if it should be to you according to your faith. If you have grace enough to grasp the whole range of blessing which the covenant of God offers you, then the whole shall be yours by a covenant of salt. He that thinks he can be off and on with God, saved today and lost to-morrow, and then saved again has a comfortless creed to defend, and a world of absurdities to meet. You are born again. Suppose that you could lose the new life which comes by the new birth, what then? I have heard of people being born again, but could they be born again, and again, and again? According to the notion of some, certain persons are born again, and again, and again, and again, and again; I do not know how many times. There is nothing in Scripture to warrant such a strange idea. If you, my friend, will come and cast yourself on Christ, and take Him to be your Saviour once for all, He will save you now with an everlasting salvation. He saith, “The water that I shall give him shall be in him a well of water springing up into everlasting life.” Jesus Himself has said it, “I give unto My sheep eternal life; and they shall never perish, neither shall any man pluck them out of My hand.” Believe for this with heroic faith. Believe for eternal salvation in Jesus Christ, who is able to work in you a lifelong escape from sin. According to your faith, so shall it be. Our sins and our fears hath He thrown into the sea. So be it. Hallelujah! Amen. ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/2188.cfm