John Gill Commentary Exodus 38:1

"And he made the altar of burnt-offering of acacia wood: five cubits was the length thereof, and five cubits the breadth thereof, foursquare; and three cubits the height thereof." — Exodus 38:1 (ASV)

Ver. 1-7. And he made the altar of burnt offering
That is, Exodus 38:2

(See Gill on Exodus 38:1).