A.T. Robertson Commentary Acts 7:33

"And the Lord said unto him, Loose the shoes from thy feet: for the place whereon thou standest is holy ground." — Acts 7:33 (ASV)

Holy ground (γη αγια). The priests were barefooted when they ministered in the temple. Moslems enter their mosques barefooted today. Cf. Joshua 5:15.

Sandal (υποδημα, bound under) is here "a distributive singular" (Hackett). Even the ground near the bush was "holy," a fine example for Stephen's argument.