The second advent is simply the second coming of the Lord Jesus Christ to this earth, which naturally implies that He has already been here once. "Now once in the end of the world hath He appeared to put away sin by the sacrifice of Himself.... And unto them that look for Him shall. He appear the second time without sin [or apart from sin] unto salvation." Heb. 9:26, 28. The second advent therefore is clearly a scriptural expression. Scripture speaks of many momentous and solemn events connected with the second coming of Christ.
Two aspects of the coming of the Lord Jesus should never be confounded: His coming for His saints, and His coming with His saints. These events may be thus illustrated. Suppose a large city revolted from allegiance to its sovereign, and refused to acknowledge his authority. After many warnings the sovereign raises an army to punish the rebels, but he knows that in that city there are many true subjects who loyally acknowledge his title and claims. When approaching the city, he secretly calls out all those loyal ones who gladly go out to meet him. He storms the city, and entering with those who have already joined him, he punishes the rebellious and rewards those who had been faithful.
Now as the coming of the sovereign would be a day of joyful deliverance to one class, so it would be followed by judgment on the others.
We find both these aspects of the coming of the Lord Jesus plainly revealed in the Scripture.
1 Thess. 4:15-18 speaks of Christ coming for His saints to their everlasting joy, and Jude 14,15 speaks of Christ coming to execute judgment on His enemies.
Notice also when Christ comes for His saints, including both the living and the dead, He will not actually come to the earth for them. The passage in 1 Thessalonians says that the saints will be caught up in the clouds to meet the Lord in the air. This is often called the RAPTURE. It will be a meeting far too sacred for the eyes of the wicked to behold—it will be in the clouds. No separation will ever take place: those that are thus caught up will be forever with the Lord.
The important aspect of the resurrection and rapture of the saints is that it is God's answer to those that believe in the all-glorious worth of His own Son. It is the bright hope of the Christian. There is no event revealed in Scripture that must take place before the rapture of the saints. They should, therefore, be expecting the return of the Lord at any moment to catch all His saints away together. (John 14:1-3; 1 Thess. 1:9, 10.)
In other Scriptures it is revealed that there will be an interval between the rapture (the catching away of the saints), and the Lord's coming to the earth. For instance, in 2 Thess. 2 we learn that the day of the Lord cannot come till the Antichrist is revealed, because the Lord is going to destroy that wicked one when He comes. Then in Rev. 13 we find that the Antichrist will cooperate with another "beast", the head of the future Roman Empire. In Dan. 9 this latter power will make a covenant with Israel, and will break the covenant in the middle of Daniel's prophetic week. All of this intimates that this apparent triumph of wickedness will spread over at least seven years, otherwise spoken of as the last week of the seventy weeks of Daniel.
That the Lord Jesus will actually come to the earth is plainly revealed in Acts 1:11, "This same Jesus, which is taken up from you into heaven, shall so come in like manner as ye have seen Him go into heaven." In Zech. 14:4 we read that "His feet shall stand in that day upon the mount of Olives, which is before Jerusalem on the east," and again, "The Lord, whom ye seek, shall suddenly come to His temple.... But who may abide the day of His coming?" Mal. 3:1, 2.
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