The apostles who wrote New Testament letters certainly affirmed their belief that Jesus might return within the lifetimes of their first-century readers. For example, James wrote:
Be patient, therefore, brethren, until the coming of the Lord. Behold, the farmer waits for the precious produce of the soil, being patient about it, until it gets the early and late rains. You too be patient; strengthen your hearts, for the coming of the Lord is at hand (Jas. 5:7-8, emphasis added).
There would have been no reason for James to admonish his readers to be patient for what could not happen within their lifetimes. He believed, however, that the coming of the Lord was “at hand.” Contextually, James wrote at a time when the church had been suffering persecution (see Jas. 1:2-4), a time when believers would naturally long for the return of their Lord.
Similarly, Paul certainly believed that Jesus might return within the lifetimes of many of his contemporaries:
But we do not want you to be uninformed, brethren, about those who are asleep, that you may not grieve, as do the rest who have no hope. For if we believe that Jesus died and rose again, even so God will bring with Him those who have fallen asleep in Jesus. For this we say to you by the word of the Lord, that we who are alive, and remain until the coming of the Lord, shall not precede those who have fallen asleep. For the Lord Himself will descend from heaven with a shout, with the voice of the archangel, and with the trumpet of God; and the dead in Christ shall rise first. Then we who are alive and remain shall be caught up together with them in the clouds to meet the Lord in the air , and thus we shall always be with the Lord. Therefore comfort one another with these words (1 Thes. 4:13-18, emphasis added).
From this we learn also that when Jesus returns from heaven, the bodies of deceased believers will be resurrected and, along with believers who are alive at His coming, will be “caught up to meet the Lord in the air” (the Rapture). Because Paul also stated that Jesus would bring with Him from heaven those who had died “in Him,” we can only conclude that at the Rapture, the spirits of the heavenly believers will be joined with their just-resurrected bodies.
Peter also believed that the coming of Christ was imminent when he wrote his first epistle:
Therefore, gird your minds for action, keep sober in spirit, fix your hope completely on the grace to be brought to you at the revelation of Jesus Christ….The end of all things is at hand ; therefore, be of sound judgment and sober spirit for the purpose of prayer….but to the degree that you share the sufferings of Christ, keep on rejoicing; so that also at the revelation of His glory, you may rejoice with exultation (1 Pet. 1:13, 4:7, 13, emphasis added).
Finally, when John wrote his letters to the churches, he too believed the end was near and that the readers of his day might well see Jesus’ return:
Children, it is the last hour; and just as you heard that antichrist is coming, even now many antichrists have arisen; from this we know that it is the last hour ….And now, little children, abide in Him, so that when He appears, we may have confidence and not shrink away from Him in shame at His coming ….Beloved, now we are children of God, and it has not appeared as yet what we shall be. We know that, when He appears, we shall be like Him, because we shall see Him just as He is. And everyone who has this hope fixed on Him purifies himself, just as He is pure (1 John 2:18, 28; 3:2-3, emphasis added).
 A few other scriptures that show Paul’s belief that Jesus could possibly return within the lifetimes of his contemporaries are Phil. 3:20; 1 Thes. 3:13; 5:23; 2 Thes. 2:1-5; 1 Tim. 6:14-15; Tit. 2:11-13; Heb. 9:28.
 Other scriptures that indicate Peter’s conviction that Jesus’ could return within the lifetimes of his contemporaries are 2 Pet. 1:15-19; 3:3-15.