Verse 20. The sun shall be turned into darkness. See Barnes "Mt 24:29".

The same images used here with reference to the sun and moon, are used also there. They occur not unfrequently, Mr 13:24; 2 Pe 3:7,10.

The shining of the sun is an emblem of prosperity; the withdrawing, or eclipse, or setting of the sun is an emblem of calamity, and is often thus used in the Scriptures, Isa 60:20; Jer 15:9; Eze 32:7; Am 8:9; Re 6:12; 8:12; 9:2; 16:8.

To say that the sun is darkened, or turned into darkness, is an image of calamity, and especially of the calamities of war; when the smoke of burning cities rises to heaven, and obscures his light. This is not, therefore, to be taken literally, nor does it afford any indication of what will be at the end of the world in regard to the sun.

The moon into blood. The word blood here means that obscure, sanguinary colour which the moon has when the atmosphere is filled with smoke and vapour; and especially the lurid and alarming appearance which it assumes when smoke and flames are thrown up by earthquakes and fiery eruptions. Re 6:12, "And I beheld when he had opened the sixth seal, and lo, there was a great earthquake; and the sun became black as sackcloth of hair, and the moon became as blood., Re 8:8. In this place it denotes great calamities. The figures used are indicative of wars, and conflagrations, and unusual prodigies of earthquakes. As these things are (Mt 24) applied to the destruction of Jerusalem; as they actually occurred previous to that event, See Barnes "Mt 24:1"

it may be supposed that the prophecy in Joel had an immediate reference to that. The meaning of the quotation by Peter in this place therefore is, that what occurred on the day of Pentecost was the beginning of the series of wonders that were to take place during the times of the Messiah. It is not intimated that those scenes were to close, or to be exhausted in that age. They may precede that great day of the Lord which is yet to come in view of the whole earth.

That great and notable day of the Lord. This is called the great day of the Lord, because on that day he will be signally manifested, more impressively-and strikingly than on other times. The word notable, epifanh, means signal, illustrious, distinguished. In Joel the word is terrible, or fearful; a word applicable to days of calamity, and trial, and judgment. The Greek word here rendered notable is also in the Septuagint frequently used to denote calamity, or times of judgment, De 10:21; 2 Sa 7:23. This will apply to any day in which God signally manifests himself; but particularly to a day when he shall come forth to punish men, as at the destruction of Jerusalem, or at the day of judgment. The meaning is, that those wonders should take place before that distinguished day should arrive when God should come forth in judgment.

{a} "The sun shall be turned into darkness" Mr 13:24; 2 Pe 3:7,10

{*} "notable" "Signal"