There came a fire, in token of God's acceptation and approbation of the priesthood now instituted, and the sacrifices now offered, and consequently of others of the like nature. See the like instances, Judges 6:21, Judges 13:19,20 1 Chronicles 21:26. And this fire now given was to be carefully kept, and not suffered to go out, Leviticus 6:13, and therefore was carried in a peculiar vessel in their journeys in the wilderness. From before the Lord; or, from the face or presence of the Lord; i.e. from the place where God was in a special manner present: either,
1. From heaven, as 1 Kings 18:38 2 Chronicles 7:1, which is oft called God's dwelling-place, as Deuteronomy 26:15 Isaiah 63:15. Or,
2. From the holy of holies, where also God is said to dwell, 2 Kings 19:15 2 Chronicles 6:2 Psalms 80:1. And what is done before the ark is said to be done before God, as 1 Chronicles 13:8,10 1 Chronicles 16:1, &c. And this may seem more probable by comparing this with Leviticus 10:2. They shouted; as wondering at, rejoicing in, and blessing God for this wonderful and gracious discovery of himself, and of his favour to them therein.