Exodus 34:33

And [till] Moses had done speaking with them,.... Not when he had done, as the Septuagint version, for then there would have been no occasion for it; but when he first began to speak to Aaron and the "rulers", and continued to speak to the congregation until he had finished what he had to say; even he did what follows, as soon as he perceived there was a glory on his face, which they could not bear to look at:he put a vail on his face; something that covered it in a good measure, a mask, or linen cloth, or some such thing.