2 Samuel 13:28

Smite Amnon. The order was given before the banquet began, and every arrangement made to render the attack successful. Though Tamar's wrong was the mainspring of Absalom's conduct, yet neither he nor his men would forget that Amnon stood between him and the crown; and Amnon, entirely off his guard, never very wise at his best, and with his senses made dull by wine, seems to have fallen an easy prey. And as soon as the murder was committed, the rest of the king's sons, though all had attendants with them, fled in dismay, not knowing what might be the extent of Absalom's purpose. It is said that they fled on mules, this being the first place in which this animal is mentioned, as the word so translated in Genesis 36:24 really means "hot springs," and is so translated in the Revised Version. The breeding of hybrids was forbidden in Le Genesis 19:19 , and probably they were procured, as were horses, by trade. Up to this time the ass had been used for riding; but now David had a favourite mule ( 1 Kings 1:33 ), and Solomon received mules as tribute ( 1 Kings 10:25 ). Horses seem to have been used chiefly for chariots.