Scripture consistently portrays God’s knowledge as conforming to the ways things really are, and part of the way things really are is temporally conditioned. Scripture never expresses the commonly-held sentiment that time is somewhat illusory. God “remembers” the past and anticipates the future. Insofar as he empowers humans to freely determine the future, this means that God waits “to see” what shall come to pass.
In Gen 2:19, after God created the animals, he brought them before Adam “to see what he would call them.” This word “to see” means something like “to discover.” God’s sovereign control of the world does not rule out an element of uncertainty about the future. God empowers humans to be genuine partners in bringing about the future, and this means that the future is, to some extent, dependent on what we do. God waits to see how humans will choose.
Another example is found when the Lord forbids the Israelites from gathering more than a day’s ration of bread from heaven when they were in the wilderness because he wants to “test them, whether they will follow my instruction or not” (Ex 16:4). By the Lord’s own admission, there would have been no point for this testing if the Lord was already certain how they would behave.
God tested Abraham to see how he would respond when asked to sacrifice Isaac (Gen 22). Moses tells the Israelites that they wandered in the wilderness for 40 years so that they Lord would know their heart (Deut 8:2). The Lord temporarily withdrew support from Israel to “find out if they would obey the command of the Lord” (Judg 3:4). God leaves Hezekiah “to himself” at one point “in order to test him and to know all that was in his heart” (2 Chron 32:31).
If we take these passages at face value, they suggest that God was not certain how they would respond to his tests before he gave them. He tested them to find this out.
Opponents of the open view often argue that God tests people not for his sake but for ours. This interpretation would be possible except that each of the verses we just examined explicitly tells us that the testing was for God, not the people being tested. An interpretation that reverses what a text explicitly says is not a viable interpretation. Others argue that if we took these verses literally we would have to deny that God possesses exhaustive present knowledge, for the passages say God wanted to know “their heart.” Since Scripture informs us that God knows all things while teaching us that God tests people to know their heart, the understanding of “heart” which this objection presupposes cannot be correct. The two teachings are easily rendered compatible by recognizing that the heart is the seat of the person’s will. To discover a person’s “heart” is to discover what their decision will be. Each of these passages, if read in context, makes this clear. The Lord tests people “to know what was in your heart, whether or not you would keep his commandments” (Deut 8:2). Since people are free agents, God wants to find out “whether they will follow my instructions or not” (Ex 16:4).
—Adapted from Satan and the Problem of Evil, pages 105-107