And you shall make an altar to burn incense upon: of acacia wood shall you make it.
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George Leo Haydock
An altar to burn incense. This burning of incense was an emblem of prayer, ascending to God from an inflamed heart. See Psalm cxl. 2; Apocalypse v. 8, and viii. 4. (Challoner)
Nothing but incense was daily offered by the high priest upon this altar. On the day of expiation he touched the four corners with blood. It stood over-against the bread of proposition. ...