In Exodus 32 the Bible records an instance of God conversing with Moses and offering Moses an alternative route to fulfill a particular prophesy/promise. The original promise was made to Abraham that Abraham’s descendants would become a great nation:

Gen 15:5 Then He brought him outside and said, “Look now toward heaven, and count the stars if you are able to number them.” And He said to him, “So shall your descendants be.”
Gen 15:6 And he believed in the LORD, and He accounted it to him for righteousness.

Fast forward 400 years later: Israel, having just been delivered from the Egyptians and en route to the Promised Land, made camp at the base of Mount Sinai. This was God’s mountain. God himself would be physically dwelling on it during Moses’ stay (Exo 19:18). After Israel established camp, the Lord commanded Moses to climb Mt. Sinai to engage in a private audience with God. Moses would speak “face to face” with God as he did multiple times throughout his life. But before Moses went up, he was instructed to set a perimeter around the mountain so that no other person would enter the mountain; Moses would be the only Israelite holy enough to meet God.

After Moses failed to return for some time, the people grew tired of waiting and began to turn to other gods. Aaron, the brother of Moses and Moses’ mouth to the people, directed the construction of a golden calf which the people would worship instead. All of Israel then pitched in their valuables to be melted in order to form this idol. They would praise this statue as the god who led them out of Egypt.

God must have been furious. Here is a people He had just saved from Egyptian bondage, a people for whom He decimated the Egyptian army, a people He led and fed on the way to a special Holy Land set apart for only them, and they have the audacity to turn from God within 40 days of setting up camp. God, seeing the corruption of his chosen people, becomes enraged. God wants to kill them all, but this might interfere with His promise to multiply Abraham’s descendants. God explains to Moses a plan B: God would kill all the rebellious Israelites and fulfill His promise to Abraham through the descendants of Moses. Because Moses was a descendant of Abraham, this would still be fulfilling God’s promise to Abraham:

Exo 32:9 And the LORD said unto Moses, I have seen this people, and, behold, it is a stiffnecked people:
Exo 32:10 Now therefore let me alone, that my wrath may wax hot against them, and that I may consume them: and I will make of thee a great nation.

Notice that God decided to scrap his original plan of using the whole of Israel for Abraham’s descendants. God himself declares his anger and desire to kill those who were unfaithful, and because of their unfaithfulness, God decided to revoke his promise to them. This is God speaking about Himself, something Christians should not take lightly. He next proceeds to command Moses to not speak to Him and to let him sit in anger. It appears that God does not want Moses to intercede on Israel’s behalf as he had done in the past. But Moses ignores God’s command and pleads on behalf of Israel.

Moses still loved his people and did not wish for their destruction. Moses next begs God to change his mind. Moses did not even stop to consider that God was unchanging or that He knew the entire future and thus was choosing the best course of action. Moses was no Calvinist. Instead, Moses tried to reason with the God:

Exo 32:11 And Moses besought the LORD his God, and said, LORD, why doth thy wrath wax hot against thy people, which thou hast brought forth out of the land of Egypt with great power, and with a mighty hand?
Exo 32:12 Wherefore should the Egyptians speak, and say, For mischief did he bring them out, to slay them in the mountains, and to consume them from the face of the earth? Turn from thy fierce wrath, and repent of this evil against thy people.
Exo 32:13 Remember Abraham, Isaac, and Israel, thy servants, to whom thou swarest by thine own self, and saidst unto them, I will multiply your seed as the stars of heaven, and all this land that I have spoken of will I give unto your seed, and they shall inherit it for ever.

So Abraham’s argument is threefold: God has already shown His favor towards Israel (this is an argument that God remain consistent), that it would look really bad for God to kill everyone that escaped from Egypt (this is an arguments about people’s perceptions about God), and that God had made a promise to Abraham (this is an argument that God’s works should not be counterproductive to His goals). Abraham tells God to repent, and God does repent:

Exo 32:14 And the LORD repented of the evil which he thought to do unto his people.

This example shows that God changes his mind based on the actions of his creatures. It shows God innovating ways to fulfill promises based on changing conditions, routes not ultimately taken. God, unless he was lying, told Moses he would consume his people. Moses, knowing God’s character because he had a personal relationship with him, understood that he can reason with God and change God’s mind. So Moses proceeded to set up a logical argument why God should not destroy his people.

The most interesting thing is that this is not an isolate instance. The exact same thing happens later after Israel was too afraid to enter the Promised Land:

Num 14:11 And the LORD said unto Moses, How long will this people provoke me? and how long will it be ere they believe me, for all the signs which I have shewed among them?
Num 14:12 I will smite them with the pestilence, and disinherit them, and will make of thee a greater nation and mightier than they.
Num 14:13 And Moses said unto the LORD, Then the Egyptians shall hear it, (for thou broughtest up this people in thy might from among them;)
Num 14:14 And they will tell it to the inhabitants of this land: for they have heard that thou LORD art among this people, that thou LORD art seen face to face, and that thy cloud standeth over them, and that thou goest before them, by day time in a pillar of a cloud, and in a pillar of fire by night.
Num 14:15 Now if thou shalt kill all this people as one man, then the nations which have heard the fame of thee will speak, saying,
Num 14:16 Because the LORD was not able to bring this people into the land which he sware unto them, therefore he hath slain them in the wilderness.
Num 14:17 And now, I beseech thee, let the power of my Lord be great, according as thou hast spoken, saying,
Num 14:18 The LORD is longsuffering, and of great mercy, forgiving iniquity and transgression, and by no means clearing the guilty, visiting the iniquity of the fathers upon the children unto the third and fourth generation.
Num 14:19 Pardon, I beseech thee, the iniquity of this people according unto the greatness of thy mercy, and as thou hast forgiven this people, from Egypt even until now.
Num 14:20 And the LORD said, I have pardoned according to thy word:
Num 14:21 But as truly as I live, all the earth shall be filled with the glory of the LORD.
Num 14:22 Because all those men which have seen my glory, and my miracles, which I did in Egypt and in the wilderness, and have tempted me now these ten times, and have not hearkened to my voice;
Num 14:23 Surely they shall not see the land which I sware unto their fathers, neither shall any of them that provoked me see it:

God repeats the exact same threat, plan B for fulfilling His promise to Abraham, and repentance. This instance concludes with God deciding to revoke one promise: that current Israel would have their Promised Land. Not only can God fulfill promises through alternative methods, He can revoke promises!