Num 13:17-24 Moses sent them to spy out the land of Canaan and said to them, “Go up into the Negeb and go up into the hill country, and see what the land is, and whether the people who dwell in it are strong or weak, whether they are few or many, and whether the land that they dwell in is good or bad, and whether the cities that they dwell in are camps or strongholds, and whether the land is rich or poor, and whether there are trees in it or not. Be of good courage and bring some of the fruit of the land.” Now the time was the season of the first ripe grapes. So they went up and spied out the land from the wilderness of Zin to Rehob, near Lebo-hamath. They went up into the Negeb and came to Hebron. Ahiman, Sheshai, and Talmai, the descendants of Anak, were there. (Hebron was built seven years before Zoan in Egypt.) And they came to the Valley of Eshcol and cut down from there a branch with a single cluster of grapes, and they carried it on a pole between two of them; they also brought some pomegranates and figs. That place was called the Valley of Eshcol, because of the cluster that the people of Israel cut down from there.
Moses’ direction to the spies was a subtle example of unbelief. When God first commissioned Moses, He told him that the land was a good and large land…a land flowing with milk and honey (Exodus 3:8). Moses told Israel that it was a good land (Exodus 13:5). There is at least a small sense here that Moses sent the spies to see if God was truthful in describing the land. Nevertheless, this was an entirely reasonable thing for Moses to do, and it reflected the curiosity of all of Israel. After all, they had never seen this land, nor had almost any Israelite for some 400 years. In some sense, this was a dangerous question to ask. If they thought the people of Canaan were strong, they might be afraid to go into the land and conquer them. If they thought they were weak, they might enter trusting in their own strength. The descendants of Anak, were there: This is the first Biblical mention of these people. They were a people of great stature (Numbers 13:33) and thought to be fierce warriors (Deuteronomy 9:2). (Guzik)
The most eager discoverer of discrepancies in the component parts of the Pentateuch need not press this one into his service, for both sides may be true: the one representing the human feebleness which originated the wish; the other, the divine compliance with the desire, in order to disclose the unbelief which unfitted the people for the impending struggle, and to educate them by letting them have their foolish way, and taste its bitter results. Putting the two accounts together, we get, not a contradiction, but a complete view, which teaches a large truth as to God’s dealings; namely, that He often lovingly lets us have our own way to show us by the issues that His is better, and that daring, which is obedience, is the true prudence. How many of us, when brought right up to some task involving difficulty or danger, but unmistakably laid on us by God, shelter our distrustful fears under the fair pretext of ‘knowing a little more about it first,’ and shake wise heads over rashness which takes God at His word, and thinks that it knows enough when it knows what He wills? (MacLaren)
Therefore God lovingly permitted the mission of the spies, and so brought lurking unbelief to the surface, where it could be dealt with. Let us beware of the one-eyed ‘prudence’ which sees only the perils in the path of duty and enterprise for God, and is blind to the all-sufficient presence which makes us more than conquerors, when we lean all our weight on it. (MacLaren)