Repent, therefore, and be converted, that your sins may be wiped away, and that the Lord may grant you times of refreshment and send you the Messiah already appointed for you, Jesus, whom heaven must receive until the times of universal restoration of which God spoke through the mouth of his holy prophets from of old.
The NAB says ..... This reference to its (the parousia) nearness is the only explicit one in Acts. Some scholars believe that this verse preserves a very early christology, in which the title "Messiah" (Greek "Christ") is applied to him as of his parousia, his second coming (contrast ÅÀ Acts 2:36). This view of a future messiahship of Jesus is not found elsewhere in the New Testament.
There are other places in the NT that refer to the second coming ... in 1 Thessalonians 4:13-18, Paul mentions it in a way that shows he expected it to happen in his lifetime ... Mark 13:26-30 speaks of Jesus' return in the time of his generation, with great power and glory ... chapeter 24 of Matthew is about the parousia ... John mentions it in Revelation 22: 12 as well.
If they truly believed that the end of the world was coming in their lifetimes, that the bad people would be punished, that good would be rewarded, that they'd be reunited with the one they loved, it must have had a profound effect on every part of their lives. And what must they have thought when they and thei friends began to die before the expected event?
One main concern of the early chriatian community was what would happen to those that died before Jesus returned. Paul's answer to this was that when Jesus returned, those who had already died would rise first and then those still alive would be snatched up to join them in union with Jesus.
Presently, some believe in a future event called the Rapture - see also Dispensationalism at Wikipedia - this view is more popularly expressed in the Left Behind books.
I think Catholic teaching is different ... there's no belief in the rapture, in which the good are taken away to heaven while the sinners remain on earth to suffer for a length of time until the final judgement. Instead, there is just one "second" coming, where Jesus reurns for everyone at the very end. And some discount even this, seeing the parousia as a metaphor for the eucharist or the second coming as actually the moment of meeting with Jesus when we die ... when Paul realized his death was near and that Jesus had not yet reeturned, he wrote “My desire is to depart and be with Christ, for that is far better” (Phil 1:23).
Who knows if there will be a parousia, and if so, when it will occur ... but it is interesting to imagine how we would live our lives differently if we believed, as the early chriatians did, that it would indeed happen before our deaths.
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- And The Sea Gave Up The Dead Which Were In It by Lord Leighton