'Cloud' in the Bible

yea, Jehovah saith unto Moses, 'Speak unto Aaron thy brother, and he cometh not in at all times unto the sanctuary within the vail, unto the front of the mercy-seat, which is upon the ark, and he dieth not, for in a cloud I am seen upon the mercy-seat.

and he hath put the perfume on the fire before Jehovah, and the cloud of the perfume hath covered the mercy-seat which is on the testimony, and he dieth not.