Rashi on Numbers 27:18/רש"י על במדבר כ״ז:י״ח

1קח 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).

2לך [TAKE] TO THEE — take one who has been examined by you, the one with whom you are familiar.

3אשר רוח בו [A MAN] IN WHOM THERE IS SPIRIT — As you requested; someone able to deal with the character of each one. (Sifrei Bamidbar 140:1).

4וסמכת את ידך עליו AND LAY THY HAND UPON HIM — Give him an interpreter, so that he will hold Halachic discourses during your life-time, — in order that people may not say about him if he does this only after your death: he dared not raise his head during Moses days but did so only at his death (cf. Sifrei Bamidbar 140:1).