"But the children rebelled against Me; they did not walk in My statutes, nor were they careful to observe My ordinances, by which, if a man observes them, he will live; they profaned My Sabbaths. So I resolved to pour out My wrath on them, to accomplish My anger against them in the wilderness. 22“But I withdrew My hand and acted for the sake of My name, that it should not be profaned in the sight of the nations in whose sight I had brought them out," (Ezek. 20:21-22).
God speaks His comments contextually in human terms in human conditioning relative to the time and situation of the people. God expresses emotion over the sin of people--emotions such as anger (Deut. 9:8), regret (1 Sam. 15:11), sorrow (1 Chron. 21:15 ), and pity (Judges 2:18). Likewise, God expresses to His people emotions in response to their sin. This is for their benefit as it enables God's people to understand and relate to Him. This is why God lets people know that He gets angry and then stays His hand from carrying out His judgment. The people need to know that they had a "close call" because they need to know God does not tolerate sin and that He will deal with it.
In Open Theism, God knows all the present exhaustively and the future only partially. So then, does God not know His own heart and how He will respond to different situations? Of course He does. Does God not know that He will withhold His own hand of judgment, or is He unaware of even His own preferences and tendencies? Does He constantly change His mind not knowing what He will do in the future because He doesn't know what choices people will make? This wouldn't make sense but that is the scenario the Open Theists would have us believe.