Charles Ellicott Commentary 2 Chronicles 7:8

"So Solomon held the feast at that time seven days, and all Israel with him, a very great assembly, from the entrance of Hamath unto the brook of Egypt." — 2 Chronicles 7:8 (ASV)

Also at the same time. —Literally, And Solomon made the feast at that time seven days. “The feast” was the Feast of Tabernacles. (See Leviticus 23:34-36.)

Seven days. —The legal time. (See Leviticus 50100) The days were counted from the 15th of the seventh month. (Compare to 1 Kings 8:65.)

The river. — Torrent or wady. Septuagint, χειμάρρους. Kings adds, before the Lord our God. So Syriac.