Charles Ellicott Commentary 2 Chronicles 3:4

"And the porch that was before [the house], the length of it, according to the breadth of the house, was twenty cubits, and the height a hundred and twenty; and he overlaid it within with pure gold." — 2 Chronicles 3:4 (ASV)

And the porch ... twenty cubits. —Hebrew, and the porch that was before the length (that is, that lay in front of the oblong main building), before the breadth of the house, was twenty cubits (that is, the porch was as long as the house was broad). This curious statement corresponds to what we read in 1 Kings 6:3: “And the porch before the hall of the house, twenty cubits was its length, before the breadth of the house.”

But the Hebrew is too unusual to pass without challenge, and a comparison of the versions suggests that we should read here: “And the porch which was before it (Syriac), or before the house (Septuagint), its length before the breadth of the house was twenty cubits.” This would involve only a slight alteration of the Hebrew text. (Compare 2 Chronicles 3:8).

And the height was one hundred and twenty. This would make the porch four times the height of the main building, which was thirty cubits. The Alexandrine manuscript of the Septuagint, and the Arabic version, read “twenty cubits;” the Syriac omits the whole clause, which has no parallel in Kings, and is further suspicious as lacking the word “cubits,” usually expressed after the number (see 2 Chronicles 3:3). The Hebrew may be a corruption of the clause, “and its breadth ten cubits.” (Compare 1 Kings 6:3).

And he overlaid it within with pure gold. —See 1 Kings 6:21.