Verse 19, 20. I will shew wonders. Literally, "I will give signs." dwsw terata. The word in the Hebrew --

HEBREW

-- mophethim, means, properly, prodigies; wonderful occurrences; miracles wrought by God or his messengers, Ex 4:21; 7:3,9; 11:9; De 4:34, etc. It is the common word to denote a miracle, in the Old Testament. Here it means, however, a portentous appearanceIn these places it does not of necessity mean miracles, but unusual and remarkable appearances. Here it is fixed to mean great and striking changes in the sky, the sun, moon, etc. The Hebrew is, "I will give signs in the heaven, and upon the earth." Peter has quoted it according to the sense, and not according to the letter. The Septuagint is here a literal translation of the Hebrew; and this is one of the instances where the New Testament writers did not quote from either.

Much of the difficulty of interpreting these verses consists in fixing the proper meaning to the expression, "that great and notable day of the Lord." If it be limited to the day of Pentecost, it is certain that no such events occurred at that time. But there is, it is believed, no propriety in confining it to that time. The description here pertains to "the last days," (Ac 2:17) that is, to the whole of that period of duration, however long, which was known by the prophets as the last times. That period might be extended through many centuries; and during that period all these events would take place. The day of the Lord is the day when God shall manifest himself in a peculiar manner; a day when he shall so strikingly be seen in his wonders and his judgments, that it may be called his day. Thus it is applied to the day of judgment, as the day of the Son of man; the day in which he will be the great attractive object, and will be signally glorified, Lu 17:24; 1 Th 5:2; Php 1:6; 2 Pe 3:12. If, as I suppose, "that notable day of the Lord" here denotes that future time when God shall manifest himself in judgment, then we are not to suppose that Peter meant to say that these "wonders" should take place on the day of Pentecost, or had their fulfillment then; but would occur under that indefinite period called "the last days," the days of the Messiah, and BEFORE that period was closed by the great day of the Lord. The gift of tongues was a partial fulfillment of the general prophecy pertaining to those times. And as the prophecy was thus partially fulfilled, it was a pledge that it would be entirely; and thus there was laid a foundation for the necessity of repentance, and for calling on the Lord in order to be saved.

Blood. Blood is commonly used as an emblem of slaughter, or of battle.

Fire. Fire is also an image of war, or the conflagration of towns and dwellings in time of war.

Vapour of smoke. The word vapour -- atmiv -- means, commonly, an exhalation from the earth, etc., easily moved from one place to another, here it means (Heb. Joel) rising columns, or pillars of smoke; and is another image of the calamities of war, the smoke rising from burning towns. It has almost always been customary in war to burn the towns of an enemy, and to render him as helpless as possible, Hence the calamities denoted here are those represented by such scenes. To what particular scenes there is reference here, it may be impossible now to say. It may be remarked, however, that scenes of this kind occurred before the destruction of Jerusalem; and there is a striking resemblance between the description in Joel, and that by which our Saviour foretells the destruction of Jerusalem. See Barnes "Mt 24:21-24".