“Neither were mindful of Thy wonders that Thou didst among them.”- Nehemiah 9:17

We are told that the Israelites were unmindful of what the Lord had done for them: “Neither were mindful of Thy wonders that Thou didst among them.” They were by this unmindfulness led into the great crime of unbelief. You think, my brethren, that if you had seen the Red Sea divided and Israel’s hosts led through, while Pharaoh’s army was drowned, you would have trusted God all your life. “Oh,” say you, “if I had been present, and really gathered the manna and eaten it, I could not, I am sure, with such a demonstration before my eyes, have ever fallen into unbelief again.” Well, I leave that question whether you would or not; having a very shrewd suspicion that your heart is by no means better than that of the ancient unbelievers. At any rate Israel soon fell back into her chronic unbelief. Within a few days after they had seen the whole host of Pharaoh destroyed, they began to murmur against God and against Moses; and though every day they ate the manna, and drank the miraculously given water, yet continually they asked, “Is the Lord among us or not?” The slightest peril, the slightest trouble to themselves, they began to think that now they were come to a difficulty out of which the Lord could not deliver them, and they cried, “Surely, He means to destroy us. He will never bring us into the promised land.” Do you know any other people like this? I need to put out my hand to touch one of the same order. If you have had idols, and have been forgiven, then you can see in this history, and in your own experience, that the Lord is ready to pardon… since the Lord forgave His people Israel, though they angered Him with their ungenerous mistrust, we see most clearly that He is “a God ready to pardon.” ~ C.H. Spurgeon

https://www.blueletterbible.org/Comm/spurgeon_charles/sermons/1272.cfm