Mark 6:9

Shod with sandals - The sandal seems to have been similar to the Roman solea, which covered only the sole of the foot, and was fastened about the foot and ankle with straps. The sandal was originally a part of the woman's dress; ancient authors represent them as worn only by women. In Matthew 10:10, the disciples are commanded to take no shoes, ὑποδηματα, which word is nearly of the same import with σανδαλια, sandals; but, as our Lord intimates to them that they should be free from all useless incumbrances, that they might fulfill his orders with the utmost diligence and despatch, so we may suppose that the sandal was a lighter kind of wear than the shoe: and indeed the word sandal, which is mere Chaldee, סנדל might be properly translated a light shoe; as it is compounded of סין sin, a shoe, (see Targum, Deuteronomy 25:9, Deuteronomy 25:10), and דל dal, thin, slender, or mean, as being made, not only lighter than the hypodema or shoe, but (probably) also of meaner materials. See many excellent observations on this subject in Martinius's Etymolog. Lexicon, under the word Sandalium.

6:9 Be shod with sandals - As you usually are. Sandals were pieces of strong leather or wood, tied under the sole of the foot by thongs, something resembling modern clogs. The shoes which they are in St. Matthew forbidden to take, were a kind of short boots, reaching a little above the mid - leg, which were then commonly used in journeys. Our Lord intended by this mission to initiate them into their apostolic work. And it was doubtless an encouragement to them all their life after, to recollect the care which God took of them, when they had left all they had, and went out quite unfurnished for such an expedition. In this view our Lord himself leads them to consider it, Luke 22:35: When I sent you forth without purse or scrip, lacked ye any thing?