The judgment of 7 times is found in Leviticus chapter 26:
verse 18: And if ye will not yet for all this hearken unto me, then I will punish you seven times more for your sins.
verse 24: Then will I also walk contrary unto you, and will punish you yet seven times for your sins.
verse 28: Then I will walk contrary unto you also in fury; and I, even I, will chastise you seven times for your sins.
The 7 times refers to 7 years that the Lord will punish an individual or a nation for sins committed. and it is fulfilled several times in the scripture:
And the children of Israel did evil in the sight of the LORD: and the LORD delivered them into the hand of Midian seven years. (Judges 6:1), punishment of the children of Israel
Let his heart be changed from man's, and let a beast's heart be given unto him: and let seven times pass over him. (Daniel 4:16), punishment of Nebuchadnezzar
Then spake Elisha unto the woman, whose son he had restored to life, saying, Arise, and go thou and thine household, and sojourn wheresoever thou canst sojourn: for the LORD hath called for a famine; and it shall also come upon the land seven years (2 King 8:1). punishment of the children of Israel again
There are some Millerites that believe God punished Israel is for 2,520 years, beginning in 677 B.C. and ending in 1843. They believe the "7 times" punishment found in Leviticus 26 is not to be taken literally, but symbolically. However, in the above three examples, the Bible teaches that 7 times means 7 literal years.
In addition, I will list some reasons as to why this 2,520 years of punishment makes no sense. During the period of 677 B.C. to 1843 A.D,
1) God sent His Son to preach good tidings, this is a blessing, not a punishment.
2) God set up His church on earth and poured out the gift of the Holy Spirit at Pentecost. This too, is a blessing and not a punishment.
3) The whole gospel went to the ends of the world at least 1 time during the Apostolic period. (blessing, not punishment)
4) Temple restored, Streets of Jerusalem rebuilt during this time by decrees from Cyrus, Darius and Artaxerxes. (blessing, not punishment)
5) Jesus taught to forgive 7 times 70 times which was 490 years. Did Jesus also teach that God punishes for 2520 years?