Regarding the words of Cush. But was he really a Cushite? Isn't it written (2 Samuel 10:9) that he had a son named Shaul, a young and handsome man? Rather, he was unique in his beauty like this Cushite who was unique in his skin color.
Similarly, you say (Numbers 12:1) concerning the Cushite woman. Was she really a Cushite? Rather, she was called a Cushite because of her actions, just as a woman can be righteous but not beautiful, or beautiful but not righteous. However, Tzipporah was both beautiful and righteous.
Some women may be beautiful to others but not to their husband, or beautiful to their husband but not to others, but Tzipporah was beautiful to her husband and to everyone. Similarly, it says (Amos 9:7) "Are you not like the children of Cush to Me?" And it is written (Song of Solomon 6:4) "You are beautiful, my love, as Tirzah." Was Shaul really a Cushite when he was told (1 Samuel 10:8) "Then go down ahead of me to Gilgal; I will surely come down to you to sacrifice burnt offerings"?
And he did as he was told. Rather, (1 Samuel 10:9) "God gave him another heart." Saul was a righteous person, but he was killed for his sins. He killed the city of Nob's priests, he had mercy on Agag, and on the best of the sheep.
Whoever has mercy on the cruel will ultimately be cruel to the merciful. And because he did not listen to Samuel, as it says (1 Samuel 13:11) "And Samuel said, 'What have you done?'" And he also said to him (1 Samuel 15:3) "Now go, attack the Amalekites and destroy all that belongs to them. Do not spare them; put to death men and women, children and infants, cattle and sheep, camels and donkeys."
But he did not do so, rather (1 Samuel 15:9) "Saul and the army spared Agag and the best of the sheep." Therefore, it is said (Psalm 7:1) "A shiggaion of David, which he sang to the Lord concerning Cush, a Benjamite." Saul was weighed against all his enemies, as it says (Psalm 18:36) "You gave me your shield of victory, and your right hand sustained me; you stooped down to make me great." This means that Saul was weighed against all his enemies.
"The Lord is my rock, my fortress, and my savior; my God is my rock, in whom I find protection. He is my shield, the strength of my salvation, and my stronghold." This is the matter. Rather, David said, "Save me from falling into his hands, and rescue me from his power." And if you do so (Psalm 35:10) "All my bones will say, 'Lord, who is like you?'"