Earlier quoted context omitted.
"The Bible predicted the end of the world in the first century." The Bible explicitly refuses to give a date for the end of the world, and proactively voids the claims of any who would. If anything the Bible anticipates a long patient delay with a purpose: "They will say, “Where is the promise of his coming? For ever since the fathers fell asleep, all things are continuing as they were from the beginning of creation.…
Paul predicted the end the world to arrive in his lifetime. He was wrong. See: 1 Thessalonians 4:15-17
It's characteristic of Paul, see Ephesians 2 for another example.
To come back to your point, if you read the rest of Paul's letter to the Thessalonians, you will find Paul's position (which is in fact Jesus' position) on the matter:
"Now, brothers and sisters, about times and dates we do not need to write to you, for you know very well that the day of the Lord will come like a thief in the night"
You can't slip a piece of paper between Paul and Jesus. Jesus himself authenticates Paul as one of his apostles.