St Peter tells us in the first century about the Lord's coming. 2Peter 3: 3-10
3 Above all, you must understand that in the last days, scoffers will come, scoffing and following their own evil desires. 4 They will say, “Where is this ‘coming’ he promised? Ever since our ancestors died, everything goes on as it has since the beginning of creation.” 8 But do not forget this one thing, dear friends: With the Lord, a day is like a thousand years, and a thousand years are like a day. 9 The Lord is not slow in keeping his promise, as some understand slowness. Instead he is patient with you, not wanting anyone to perish, but everyone to come to repentance.