Comentario sobre Números 27:18

קח לך TAKE TO THEE [JOSHUA] — take him through fine words, saying,“Fortunate are you that you have merited to lead the children of the Omnipresent!” (cf. Sifrei Bamidbar 92 on 11:16).

איש אשר רוח בו; someone who is ready and worthy to be presented to the King of Kings. We have a similar expression in Exodus 31,6 ובלב כל חכם לב נתתי חכמה, where the Torah speaks about people equipped, endowed with the necessary amount of Holy Spirit to enable them to perform the tasks allocated to them.

ויאמר ה׳ אל משה, G'd said to Moses, etc. Why did G'd say to Moses: "take for yourself?" What did G'd mean when He said of Joshua that he was איש אשר רוח בו, "a man possessed of spirit?" Is there then any man devoid of spirit? Besides, what precisely is the significance of וסמכת את ידך "you will place your hand?" What will this achieve? We must understand the whole verse in terms of Moses' request to G'd previously, as we explained. When G'd said to Moses: "take for yourself," the meaning is: "I want to put at rest your fears. If you will appoint Joshua the Israelites will have a leader who has a similar spirit to yours, i.e. his soul emanates from a background not much different than yours." This is why G'd underlined that Joshua was a man אשר רוח בו. He shares many of the psychological factors which predominate in this generation. G'd ordered Moses to place his hand on Joshua to transfer some of the qualities of Moses' soul to Joshua. At the end of the instruction (verse 20) G'd adds: "in order that the whole congregation of the children of Israel will hear." Seeing these words are next to the words "and you transfer from your authority to him," they mean that Moses transferred some of the properties of his soul to Joshua, i.e. that he too would become a root of their combined souls. This would ensure that the people would accept Joshua's authority over them. When the Torah refers to the "whole congregation of the children of Israel," it refers to the spiritual elite of the people as being pleased with the new leader Moses would appoint now.