Malbim (Yeshayah 36:6): If you rely on people, you rely on Mitzrayim, like Malchei Yisrael relied on it (Perakim 30, 31), it is like a fragile reed.

Rashi: When one leans on a fragile reed, and it breaks in his hand, the [pointy] exuding strands [where it broke] puncture his hand.

Radak: A reed broken at its end, when he leans on it, the [pointy] exuding chips enter his hand [and puncture it].

Malbim (Yeshayah 36:6): There are two losses through relying on a fragile reed for support. (a) He does not support himself with his legs ¹ . (b) The reed breaks, and punctures his hand. So those who rely on Pharaoh, they slacken from acting to save themselves, and he comes to collect tax from them. He does not help. He only harms!