Jérémie 9:22 Midrash : Otzar Midrashim, Midrash Tanchuma, Midrash Tanchuma Buber & Bamidbar Rabbah

It is written "Let not the mighty man glory in his might" (Jeremiah 9:22) - this refers to King David. They said that when David would fight, he would throw [his spear] and kill eight hundred men with one throw, and he would unsheathe his sword against three hundred men at once. When David saw this, he would become arrogant and say "There is none like me in the world, and after me there will be none like me." The Holy One Blessed Be He said to him "Do not become arrogant in your might, you are numbered." And now you will see that it does not come from your might. What did the Holy One Blessed be He do? He made a gazelle pass before him, and Avishai was sitting with him. David and Avishai went after it until they went too far after the gazelle, and they got lost on the road, and the strap of Avishai's sandal came undone. While he was tying it, David went ahead until he saw a beautiful tower. He went and entered it, and saw an old woman, the mother of Goliath the Philistine, and she was sitting and spinning wool. She recognized him as the one who killed her son Goliath the Philistine, but he did not recognize her. She went and cut her thread, and said "My son, pass me my distaff." He said to her "By your life, my lady!" When he reached to take the distaff, she immediately hid it in her lap, and placed him under the legs of the bed she was sitting on, in order to break all his bones. Immediately, God showed David that He has neither forgetfulness nor favoritism, and He made a vat fall under him into which David fell. When the brother of Goliath the Philistine came, his mother immediately went out to meet him and said "My son, do you know what I have captured?" He said "No." She said "Here, I have captured David who killed your brother." He said to her "My mother, what have you done to that wicked man? Give him to me and I will kill him." She said "Go and see him under the legs of the bed, where I have broken all his bones." He went and saw him sitting in the vat. When he saw this, he said to his mother "He lives!" He went and took his spear, and went into the sand, and placed his spear in the ground with its blade towards the sky in order to catch David on his spear. He took David and threw him up in the air with his spear underneath, but God made David hover in the air. Meanwhile, Avishai arrived and saw the whole incident. He went to the brother of Goliath the Philistine and said to him "Give me your spear and I will kill him." He said "Take it." When he took it, Avishai went and killed that wicked man. Then immediately David fell down, and they returned to their place. Then they said "Where is the might? It is not his, but God's." And this is the meaning of the verse "And Avishai helped David and struck the Philistine."

(Numb. 32:1:) “Now the Children of Reuben and the Children of Gad] had much livestock.” Let our master instruct us: How many good gifts were created in the world?¹⁴Numb. R. 22:7. Thus have our masters taught: The Holy One, blessed be He, created three gifts in the world: wisdom, strength, and wealth. A person meriting one of them receives what is most desirable in the whole world. A person meriting wisdom has merited everything. A person meriting strength has merited everything. A person meriting wealth has merited everything. When? When they are gifts of the Heavens and come from the power of the strength of the Holy One, blessed be He. But human strength and wealth are nothing; for thus has Solomon stated (in Eccl. 9:11), “Again I saw that under the sun [the race does not belong to the swift, nor the battle to the strong, nor bread to the wise, nor even wealth to the discerning, nor even favor to the knowledgeable].” Thus also has Jeremiah stated (in Jer. 9:22), “Thus says the Lord, ‘Let not the wise boast in their wisdom, [nor the strong boast in their strength, nor the wealthy boast in their wealth].’” So these gifts, when they do not come from the Holy One, blessed be He, will finally be cut off from them. The sages taught, “Two wise men arose in the world, one from Israel and one from the nations of the world. Ahitophel was from Israel, while Balaam was from the nations of the world; but both of them were lost from this world and from the world to come. Two strong men arose in the world, one was from Israel and one from the nations of the world. Samson was from Israel, while Goliath was from the nations of the world; but both of them were lost from the world. Two wealthy men arose in the world, Korah from Israel and Haman from the nations of the world; but both of them were lost from the world. Why? Because their gift was not from the Holy One, blessed be He. Rather they grabbed it up for themselves. So also do you find with the Children of Gad and the Children of Reuben that they were very wealthy and had a lot of livestock. But they loved their money and resided outside the Land [of Israel as a result]. For that reason they were the first of the tribes to go into exile, as stated (in I Chron. 5:26), ‘and he carried them into exile, i.e., the Reubenites and the Gadites […].’ Who brought [the exile] upon them? [It happened] because they had separated themselves from their siblings for the sake of their livestock. And where is it shown? From what they read on the subject (in Numb. 32:1), ‘Now the Children of Reuben and the Children of Gad had much livestock.’”

(Numb. 32:1:) NOW THE CHILDREN OF REUBEN <AND THE CHILDREN OF GAD> HAD MUCH LIVESTOCK…. Let our master instruct us: How many good gifts were created in the world?¹⁸Tanh., Numb. 9:5; Numb. R. 22:7. [Thus have our masters taught: The Holy One created three gifts in the world:] wisdom, strength, and wealth. A person meriting one of them receives what is most desirable in the whole world. When? When they come from the Holy One and come through the power of the Torah. But human strength and wealth are nothing, for thus has Solomon stated (in Eccl. 9:11): AGAIN I SAW THAT UNDER THE SUN THAT THE RACE DOES NOT BELONG TO THE SWIFT, NOR THE BATTLE TO THE STRONG, NOR BREAD TO THE WISE, NOR EVEN WEALTH TO THE DISCERNING, <NOR EVEN FAVOR TO THE KNOWLEDGEABLE,> FOR TIME AND AFFLICTION (i.e., death) ENCOUNTER ALL OF THEM. Thus also has Jeremiah stated (in Jer. 9:22 [23]): THUS SAYS THE LORD: LET NOT THE WISE BOAST IN THEIR WISDOM, NOR THE STRONG BOAST IN THEIR STRENGTH, NOR THE WEALTHY BOAST IN THEIR WEALTH. So these gifts, since they do not come from the Holy One, will finally be cut off from them.