For an introduction to this series, click here.
Here we have the conclusion of this book. The first part of this chapter continues the thought of the previous chapter concerning the Rapture:
"Now concerning the times and the seasons, brothers, you have no need to have anything written to you. For you yourselves are fully aware that the day of the Lord will come like a thief in the night. While people are saying, 'There is peace and security,' then sudden destruction will come upon them as labor pains come upon a pregnant woman, and they will not escape. But you are not in darkness, brothers, for that day to surprise you like a thief." (5:1-4)
The Rapture is not something we should be worried about. The Lord will come when the time is right and we will know it when He comes. He is not going to hide somewhere.
"So then let us not sleep, as others do, but let us keep awake and be sober. For those who sleep, sleep at night, and those who get drunk, are drunk at night. But since we belong to the day, let us be sober, having put on the breastplate of faith and love, and for a helmet the hope of salvation. For God has not destined us for wrath, but to obtain salvation through our Lord Jesus Christ, who died for us so that whether we are awake or asleep we might live with him." (5:6-10)
In virtually every epistle, Paul includes this warning: to be sober. He gives different reasons, but the admonishment is still the same. Life is serious. Of course it is fine to have a good time and we need to relax and refresh ourselves from time to time, but overall, Christians should not be characterized by an attitude of pursuing fun all the time and not taking life seriously.
As a side note, some people say that the phrase "God has not destined us for wrath" is a proof text for the "pre-tribulational" rapture. I think if you read it in context, it becomes obvious that this passage is talking about us as believers not being condemned to hell.
"We ask you, brothers, to respect those who labor among you and are over you in the Lord and admonish you, and to esteem them very highly in love because of their work. Be at peace among yourselves. And we urge you, brothers, admonish the idle, encourage the fainthearted, help the weak, be patient with them all. See that no one repays anyone evil for evil, but always seek to do good to one another and to everyone. Rejoice always, pray without ceasing, give thanks in all circumstances; for this is the will of God in Christ Jesus for you. Do not quench the Spirit. Do not despise prophecies, but test everything; hold fast what is good. Abstain from every form of evil. Now may the God of peace himself sanctify you completely, and may your whole spirit and soul and body be kept blameless at the coming of our Lord Jesus Christ. He who calls you is faithful; he will surely do it." (5:12-24, ESV)
These are some general things that are very hard to actually live out in our daily lives. If we could obey just one of these commands completely, the way the Lord wants us to, our lives would be so different. Now that isn't an excuse, but I know for me particularly, it is hard for me to "rejoice always." Because there are things in life that don't cause me to rejoice.
I think if you look at it in context (isn't it amazing how much simpler things are when you read more than one verse at a time) it becomes obvious that "Abstain from every form of evil" is one of the most abused verses in the Bible. I have heard that verse used to justify all sorts of ideas, from saying that you shouldn't eat in a restaurant that serves alcohol to not going to a movie rental store. (My, how the world has changed in 8 years!) In context, Paul is talking about true and false doctrine. We are told not to despise prophecies. In other words, don't reject any teaching out of hand just because of who is teaching or whatever. Then we are told to prove all things, hold fast to the good and reject what is bad. Simple. The Bible speaks for itself, and we would do well to follow the clear teaching in the passage above and forget the opinions of man piled onto one particular phrase.