Midrash su Deuteronomio 34:9

He gives wisdom to one who possesses wisdom and understanding and knowledge in all kinds of work. Similarly, you find that this was so in the case of Joshua: Joshua the son of Nun was full of the spirit of wisdom (Deut. 34:9), for he already possessed wisdom. This may be compared to a shopkeeper to whom a man goes to purchase wine, honey, oil, or brine. The shopkeeper smells the odor that comes from the bottle, and if it is of wine he pours wine into it, and he does likewise with honey, oil, or brine. When the Holy One, blessed be He, observes that a man has the spirit of wisdom within him, He fills him with additional wisdom. Hence He hath filled him with the spirit of wisdom, since he already possesses some.

The Temple was similarly constructed by means of these three attributes, as it is said: He was the son of a widow of the tribe of Naphtali, and his father was a man of Tyre, and he was filled with wisdom, understanding, and skill (I Kings 7:14). Similarly, the Temple will be rebuilt in the future with these three attributes, as is said: Through wisdom is a house builded, and by understanding it is established; and by knowledge are the chambers filled with all precious and pleasant riches (Prov. 24:3–4). Therefore, And He hath filled him with the spirit of God. Where did all this wisdom come from? From the spirit of God. And He filled him with the spirit of God alludes also to Joshua, who descended from the tribe of Ephraim, as it is written: And Joshua the son of Nun was full of the spirit of wisdom (Deut. 34:9). And it refers as well to Othniel the son of Kenaz, who came from the tribe of Judah, since it is written about him: And the spirit of the Lord came upon him, and he judged Israel (Judg. 3:10). All this happened because Moses blessed the tribe: And this for Judah, and he said: “Hear, Lord, the voice of Judah, and bring him in unto his people; his hands shall contend for him, and Thou shalt be a help against his adversaries” (Deut. 33:7). When they become involved in difficulties, You shall be a help to them.

Another interpretation (of Exod. 31:3): AND I HAVE FILLED HIM <WITH THE DIVINE SPIRIT IN WISDOM, UNDERSTANDING, AND KNOWLEDGE >. Joshua, who came from the tribe of Joseph, was also filled with the spirit of wisdom, as stated (in Deut. 34:9): NOW JOSHUA BEN NUN WAS FILLED WITH THE SPIRIT OF WISDOM. Also Othniel ben Kenaz, who was from the tribe of Judah, was filled with the spirit of God, as stated (in Jud. 3:10): AND THE SPIRIT OF {GOD} [THE LORD] CAME UPON HIM. Now all this was by virtue of the blessing with which Moses blessed this tribe, as stated (in Deut. 33:7): AND THIS IS FOR JUDAH, [AND HE SAID: HEAR, O LORD, THE VOICE OF JUDAH….] The Holy One said to Israel: in this world my Spirit shall instill wisdom within you, but in the world to come I <myself> will teach you, as stated (in Ezek. 37:14): I WILL PUT MY SPIRIT WITHIN YOU SO THAT YOU MAY LIVE.