'Sandal' in the Bible

he who comes after me, the thong of whose sandal I am not worthy to unloose.

And the Lord said to him, Loose the sandal of thy feet, for the place on which thou standest is holy ground.

And as John was fulfilling his course he said, Whom do ye suppose that I am? I am not he. But behold, there comes one after me, the sandal of whose feet I am not worthy to loose.