The force would be: 'having (or, when he had) put a covering over his face.' Ver. 35 would, I think, imply that as long as he was getting these divine communications he kept the veil over his face except when he went into the sanctuary. 2Cor. 3, which has been alleged for the opposite view, proves this, for it alludes to the fact in saying of the veil on Israel's heart, that when they turn to the Lord it will be taken off.