as you quoted...nor shall ever be again.Fact is, nowhere in Scripture can we find this seven-year tribulation you continue to promote. It defies logic to ask one to prove something from the Bible that is nowhere to be found in the Bible. What I believe the Bible teaches is that the church, representing the Kingdom of God on earth would suffer "great tribulation" such as nothing like it before, nor shall ever be again from the time Christ came to earth a man proclaiming the Kingdom of God had come. Faithful saints throughout every generation have suffered and shall suffer great tribulation in this life as the Kingdom of God is being completed, and it will not end until Christ comes again.
If your interpretation is correct then the bible errored as men have seen and been through tribulation....and some men have seen more troubling tribulation than others which you said...nor shall ever be again. But they did.