Matthew 24:21-22

for that will be 'a time of great distress, the like of which has not occurred from the beginning of the world down to the present time'--no, nor ever will again.

Mark 13:19

For those days will be a time of distress, the like of which has not occurred from the beginning of God's creation until now-- and never will again.

Acts 2:20

The sun shall become darkness, and the moon blood-red, Before the Day of the Lord comes--that great and awful day.

Romans 11:26

And then all Israel shall be saved. As Scripture says--'From Zion will come the Deliverer; he will banish ungodliness from Jacob.

Revelation 6:17

for the great Day of their Wrath is come, and who can stand to meet it?'

Treasury of Scripture Knowledge

Summary

Alas! for that day is great, so that none is like it: it is even the time of Jacob's trouble; but he shall be saved out of it.

Bible References

For

Acts 2:20
The sun shall become darkness, and the moon blood-red, Before the Day of the Lord comes--that great and awful day.
Revelation 6:17
for the great Day of their Wrath is come, and who can stand to meet it?'

So

Matthew 24:21
for that will be 'a time of great distress, the like of which has not occurred from the beginning of the world down to the present time'--no, nor ever will again.
Mark 13:19
For those days will be a time of distress, the like of which has not occurred from the beginning of God's creation until now-- and never will again.

But

Romans 11:26
And then all Israel shall be saved. As Scripture says--'From Zion will come the Deliverer; he will banish ungodliness from Jacob.