Who Sent Whom and Why

Rashi:"Send for yourself men"
Why is the section dealing with the spies juxtaposed with the section dealing with Miriam[’s sin and punishment]? Because she was punished over matters of slander, for speaking against her brother, and these wicked people witnessed it but did not learn their lesson.

"Send for yourself"
According to your own understanding. I am not commanding you, but if you wish, you may send. Since the Israelites had come to Moses and said, "Let us send men ahead of us," as it says, "All of you approached me…" (Deut. 1:22), Moses took counsel with the Shechina. He [G‑d] said, "I told them that it [the Land of Israel] is good, as it says, ‘I will bring you up from the affliction of Egypt…[unto a land flowing with milk and honey].’ (Exod. 3:17) By their lives! Now I will give them the opportunity to err through the words of the spies, so that they will not inherit it."

Baal HaTurim:"Send for yourself men"
The final letters of these 3 words ['shelach lecha anashim'] spell the term chacham/wise man, for they [these men] should be distinguished, wise and righteous. The gematria of Shelach/ Send forth is 338, which hints to the year the nation would be sent out in exile. The 1st Temple was destroyed in the year 3338, hinted to in the verse "send them away from My Face [the Shechina] and let them go." (Jer. 15:1)

Maggid Mesharim: In order to hint that G‑d put the request to send spies into their hearts, the text does not say that all of them approached Him, as it says (Deut. 1:22), "And you came near unto me (Moses) every one of you, and said: 'Let us send men before us, that they may search the land for us, and bring us back word of the way by which we must go up, and the cities unto which we shall come." With regard to Moses, he commanded them to send the heads, that is the wisest among them, so Joshua would prove he was great in Torah matters as well as the others. Therefore, he did not command to send the princes involved in the dedication of the altar for fear that their hearts would rise in pride and consequently they would not fulfill their mission properly.

Or HaHayyim: "Send for yourself"
Why is the word "for you" written here?

• G‑d's command or consent for Moses to send out spies was G‑d agreeing for Moses to send out spies provided their mission was what Moses understood it to be, like discovering hidden Canaanite treasures, but not if it was to determine if the land could be captured by Israel.
• It may relate to the definition of the men of valor. G‑d told Moses that these men were righteous ‘for you,’ as long as they were in Moses' presence, facing him.
• A simpler way of explaining it is, "In your eyes, Moses, they may be righteous but in My eyes they are wicked". They could be called wicked because at the beginning of the mission they shared the view of the Israelites as a whole that they should investigate if the land could be conquered—a lack of faith in Gd.
• G‑d wanted this mission to be known as something Moses had initiated, not as something He Himself had done.
• "For you" means that the mission ought to be the one Moses perceived it to be, in contrast to what Israel wanted.
• It could allude to what our sages said that Moses complained about the ways of G‑d's conduct after the fate of Israel worsened after his appointment as their leader.

Ramban: It appears to me from the language of the Torah that Moses did not in fact consult the Shechina if he should send spies, but the meaning of ’send for yourself’ is that the people had already decided to send spies.

The Lubavitcher Rebbe: A life of Jewish observance has 2 factors:
Firstly, we follow direct commands specified in the Code of Jewish Law. In those areas not directed by Jewish Law, we must use our own discretion to determine the most appropriate action, as G‑d told Moses here. Each approach has its own unique advantage. By issuing commands, G‑d chooses us as His partner, despite the fact we are so infinitely inferior to Him. The command makes a bridge that connects us with G‑d in a way that would not otherwise be possible.
However with a relationship of commands alone, we would remain a passive partner, who is always told by the Senior Partner what to do. Thus part of our mission is left to our discretion, so we can become an active "equal partner" with G‑d to so speak, to make some decisions for ourselves. (Likutei Sichot 13:42-3)

Zohar Shelach 157:
Come and see: If you think Moses did not know at that time that he would not enter the land of Israel, it is not so. He most certainly knew and he wished to know about it before he departed; therefore, he sent spies. Since they did not report to him properly, he did not send more until G‑d showed [the Land] to him, as it is written: "Go up onto this Mount Avarim...and behold the Land." (Deut. 32:49) It is also written: "And G‑d showed him all the land." (Deut. 34:1) Not only this, but Moses was shown all those who were destined to arise in each successive generation,
As soon as Moses began to send out his spies, what did he say to them? "Whether there is a tree in it." (Num. 13:20) What is the reason that he said this? Do you think that he did not know? However, this is what Moses said: If "there is a tree in it," I know that I will enter the land. What tree? That is the Tree of Life. It was not there, but rather in the supernal Garden of Eden. He said to himself: If that tree is in it, I will enter there and if not, I cannot enter.
Rabbi Yehuda opened saying, "Like the cold of snow in the time of harvest, so is a faithful messenger to those who send him: for he refreshes the soul of his master." (Prov. 25:13) "Like the cold of snow in the time of harvest": it is good for the body and soul. "A faithful messenger to those who send him": these are Caleb and Phineas, who were faithful messengers of Joshua. "For he refreshes the soul of his master": they returned the Shechina to rest on Israel, and She did not part from them.