John Gill Commentary 2 Chronicles 7

Now when Solomon had made an end of praying
The prayer recorded in the preceding chapter:

the fire came down from heaven and consumed the burnt offering and the
sacrifices ;
which was the token God gave of his acceptance of them, of which there had been several instances before, (Leviticus 9:24) , (1 Kings 18:38) (1 Chronicles 21:26) ,

and the glory of the Lord filled the house ;
the glory of the Shechinah of the Lord, as the Targum, see (1 Kings 8:11) .

And the priests could not enter into the house of the Lord , &c.] They went in to carry the ark there, but not being able to stand to minister, they came out, and could not re-enter:

because the glory of the Lord had filled the Lord's house ; both the holy place, and the holy of holies, see (1 Kings 8:10 1 Kings 8:11) .

And when all the children of Israel saw how the fire came down ,
&c.] From heaven upon the sacrifice, and consumed it, which was all visible to the eye; or it may be this was a distinct fire from the former, since it seems to have come down upon the house, and so may denote a bright, shining, glorious light; the same with what follows:

and the glory of the Lord upon the house ;
for not only the house was filled with the glory, but there was a bright stream of light and glory over it, very dazzling and surprising:

they bowed themselves with their faces to the ground upon the pavement ;
of the great court, where they were assembled:

and worshipped and praised the Lord :
worshipped him by praising him:

saying, for he is good ;
in his nature, promises, and blessings; is good, and does good:

for his mercy endureth for ever ;
this was the close of their song of praise.

Ver. 4,5. Then the king and all the people
Of these two verses, (See Gill on 1 Kings 8:62), (See Gill on 1 Kings 8:63).

(See Gill on 2 Chronicles 7:4).