Deuteronomy 33:22

Here is, I. The blessing of Dan, Deu 33:22. Jacob in his blessing had compared him to a serpent for subtlety; Moses compares him to a lion for courage and resolution: and what could stand before those that had the head of a serpent and the heart of a lion? He is compared to the lions that leaped from Bashan, a mountain noted for fierce lions, whence they came down to leap upon their prey in the plains. This may refer either, 1. To the particular victories obtained by Samson (who was of this tribe) over the Philistines. The Spirit of the Lord began to move him in the camp of Dan when he was very young, as a lion's whelp, so that in his attacks upon the Philistines he surprised them, and overpowered them by main strength, as a lion does his prey; and one of his first exploits was the rending of a lion. Or, 2. To a more general achievement of that tribe, when a party of them, upon information brought them of the security of Laish, which lay in the furthest part of the land of Canaan from them, surprised it, and soon made themselves masters of it. See Jdg 18:27. And, the mountains of Bashan lying not far from that city, probably thence they made their descent upon it; and therefore are here said to leap from Bashan. II. The blessing of Naphtali, Deu 33:23.

— Matthew Henry's Concise Commentary (public domain)

Dan is a lion's whelp--His proper settlement in the south of Canaan being too small, he by a sudden and successful irruption, established a colony in the northern extremity of the land. This might well be described as the leap of a young lion from the hills of Bashan.

— Jamieson-Fausset-Brown Commentary (public domain)