Common argument that is heard often. Is it true or is it totally backwards?
Those who understand what God has accomplished and those who can "see" the Kingdom of God here on earth, totally understand what that "hope" was that the dead in Christ and the first century saints were waiting for at the end of the age. We, as New Covenant children of God know that we don't have to hope and wait for these promises because we already have them now.
The irony is, if Christ DID NOT return in the first century, then you actually have no hope. Why? Well because if He didn't fulfill all of His promises then we can certainly question His authority and His divinity. I won't quote all of the assurances He made because this post would be 10 pages long but He did say...
"For the son of Man will come in the glory of His Father with His angels, and then He will reward each according to his works. "Assuredly, I say to you, there are some standing here who shall not taste death till they see the Son of Man coming in His kingdom.” Matthew 16:27-28
"When they persecute you in this city, flee to another. For assuredly, I say to you, you will not have gone through the cities of Israel before the Son of Man comes." Matthew 10:23
"Truly I say to you, this generation shall not pass until ALL these things are fulfilled" Matthew 24:32
And on and on and on....
If He didn't come, then He was wrong. Therefore you can truly question everything you believe.
Thankfully He did fulfill every last promise He made. Rest assured He is exactly who He said He is.