'Untie' in the Bible

And he was preaching, and saying, “After me One is coming who is mightier than I, and I am not fit to stoop down and untie the thong of His sandals.

and *said to them, “Go into the village opposite you, and immediately as you enter it, you will find a colt tied there, on which no one yet has ever sat; untie it and bring it here.