SADDLE (Heb. mercāv, a riding seat). The verb habhash, “to bind on,” is used of getting a beast (always a donkey) ready for riding (Gen.22.3; Num.22.21; Judg.19.10; 2Sam.16.1; 2Sam.17.23; 2Sam.19.26; 1Kgs.2.40; 2Kgs.4.24). Donkeys were not ridden with saddles. A donkey carrying a heavy burden had a thick cushion on its back to relieve the pressure.

SADDLE (מֶרְכָּב, H5323, חָבַשׁ, H2502, covering, riding seat; verb to wrap firmly, to tighten the girths).

Perhaps an early invention of the Persians, the saddle served both as a carriage for riders and as a covering to prevent the animal’s back from chafing. It is used in the former sense in Leviticus 15:9 where the rule on uncleanness extends also to the “saddle” used by the unclean person. The tr. of merkav here is uncertain; it may mean “chariot.” Ordinarily, as is indicated in the record of Abram going up to Mt. Moriah with Isaac (Gen 22:3) and Balaam setting out to curse Israel (Num 22:21), it was the ass that was saddled. In one instance, that of Laban pursuing his fleeing daughters (Gen 31:22), reference is made to the saddling of a camel. The camel’s “furniture” (Gen 31:34) seems to have been a basket-like saddle (כַ֥ר).

International Standard Bible Encyclopedia (1915)

sad’-’-l: As noun (merkabh, "a riding seat") the word occurs in Le 15:9 (margin "carriage"); ordinarily it is used as a verb (chabhash, literally, to "bind up" or "gird about"), to saddle an ass (Ge 22:3; Nu 22:21; Jud 19:10, etc.).