John Gills Exposition of the Bible Commentary - Exodus 25:17
And thou shall make a mercy seat of pure gold ,.... Or "covering" F14 כפרת "opertorium", Montanus; "tegmen sive operimentum", Vatablus; "operculum", Piscator. ; so Jarchi and Aben Ezra; for so the word properly signifies; and what is meant was no more than a cover of the ark, which was open at the top, and this was the lid of it, and exactly answered to it, as appears by the dimensions afterwards given of it; and because the root of this word in one form signifies to propitiate or... read more
Matthew Henry's Complete Commentary - Exodus 25:10-22
The first thing which is here ordered to be made is the ark with its appurtenances, the furniture of the most holy place, and the special token of God's presence, for which the tabernacle was erected to be the receptacle. I. The ark itself was a chest, or coffer, in which the two tables of the law, written with the finger of God, were to be honourably deposited, and carefully kept. The dimensions of it are exactly ordered; if the Jewish cubit was, as some learned men compute, three inches... read more