I Thes. 5:4 alludes to believers not being surprised by the coming Day of the Lord. I’ve always thought that it means that we will not be caught off guard because we are prepared, we have Christ. Is there more?
I disagree that “having Christ” fulfills Paul’s statement in 1 Thes. 5:4. Lots of people “have Christ” but don’t have a clue as to what Bible prophecy says about the End Times. They may be saved but they have made no preparation for the life to come. They’re like the people Jesus criticized at His first coming.
“When evening comes, you say, ‘It will be fair weather, for the sky is red,’ and in the morning, ‘Today it will be stormy, for the sky is red and overcast.’ You know how to interpret the appearance of the sky, but you cannot interpret the signs of the times.” (Matt. 16:2-3).
People like this risk missing out on blessings that could have been theirs had they followed the Lord’s instructions on preparing for the life to come. Many will enter eternity with nothing to show for their life as Christians, but “as one escaping the flames” (1 Cor 3:10-15).