Midrasch zu Jechezkiel 7:20

The Holy One, blessed be He, said: He has made his attack against the heavenly beings, (and God) will send against them insignificant things, to teach them that the power of their might is nought. When Titus, the wicked, entered the Holy of Holies, he said: No adversary || or enemy can prevail against me. What did the Holy One, blessed be He, do to him? He sent a single gnat, and it went into his nostril, and it ate its way into his brain. That gnat became like a young pigeon, weighing two pounds, to teach him that there was nothing at all in the might of his power. When Israel walked in the Holy of Holies with a proud heart, and said: No adversary or enemy is able to stand before us. What did the Holy One, blessed be He, do to them? He sent against them a man, proud and like one sifting the sea, Nebuchadnezzar, whose name was Kabbīr Mayim (like one sifting the sea), to teach; "For by strength shall no man prevail" (1 Sam. 2:9).