OPPOSITES ATTRACT
We often think that predestination and free will are enemies, like Achilles and Hector battling for the fate of Troy.  However, we might want to consider what the Bible says about destiny and choice.  An example might be 1 Thessalonians 5.1-11.

  The city was named after Thessalonica, the sister of Alexander the Great.  When Alexander's father Philip of Macedon conquered the Thessalonians, his daughter was born on that day.  He named her after them.  When she married Cassander, she rebuilt the city which still stands today.
  The Jews had a synagogue there.  The Jewish community knew the Day of the Lord was coming.  But the other people of the city lived as if life goes on as usual.  Paul here predicts that the Day of the Lord will come on the Thessalonians and--they will not escape, 1 Thes. 5.3

  Paul says the Christians in Thessalonica know this--you yourselves know this full well, 1 Thes. 5.2.  They know what is going to happen beforehand, that the Day of the Lord is predestined.  And yet Paul does not say to stand still, but he calls them to action:
  Let us not sleep as others do,
  let us be alert..
  let us be sober..1 Thes. 5.6.

Paul then says--God has not destined us for wrath but for obtaining salvation...therefore encourage one another and build up one another, as you also are doing, 1Thes. 5.11.  The believers are destined for obtaining salvation but Paul does not say, Rest on your eternal security, my friends.  He encourages them to use their free will to act.

  Probably the reason salvation and action go together is that the world will end.  At some point the times will be too late for evangelism. Salvation is not retirement to the rest home.  Christians don't end the evening playing gin rummy; Christians call upon the Spirit of God to share the gospel because the time is always short for someone.

  At the end of 1 Thes. 5, Paul has 18 consecutive verses of what the Thessalonians should do.  Some of them are well-known--
  rejoice always
  pray without ceasing
  in everything give thanks, for this is the will of God for you
  do not quench the spirit
and there are others.  What this means is that our predestination, our salvation is put to work.  In Ephesians the believers are to--
  walk in a manner worthy of your calling
  show forbearance to one another
  be renewed in the spirit of your mind
  put on the new self
  be kind to one another
  forgiving one another

  These aren't all of what Paul says to do by the dedication of your will to your calling, but they are enough to understand that Paul's concept of predestination is not void.  In Romans 16 the list of what the Christian is called to do with his or her calling is even longer.
  Evidently a believer's calling is the power of the Spirit to live the Christian life.  We can immediately remember the woman caught in adultery of John 8.  When the accusers leave, Jesus says--Go and sin no more.  Would He say that if she could not do so?  In Matthew 6.1 Jesus says--Beware of practicing your righteousness before men...  So we see there is the practice of righteousness.  After Jesus says this He mentions fasting, praying, giving alms, forgiving, laying up treasure in heaven, serving God, trusting God without anxiety, seeking the kingdom of God and His righteousness.  Then in chapter 7 He says, don't judge, ask in prayer, enter the narrow gate, beware of false prophets, do the will of God, and finally, act upon His words.

Predestination is a call to action as free will is a call to the knowledge of God.  The difference is the man who hears--predestination-- and the man who hears and then acts--predestination and free will.  To the Ephesians Paul is praying that they would know--
  What is the hope of His calling...
of the saints, Eph. 1.18.  This calling is not to rest in salvation but to act upon it.  So in Matt. 25 Jesus says He will come back in glory.  He will put His sheep on His right hand, the goats on His left.  This had been predicted by Jesus.  The sheep were predestined for the kingdom of heaven, as it was--prepared for you from before the foundation of the world.  They were predestined so that exercising free will to take care of the least of Jesus' brothers is what Peter calls--make certain about His calling and choosing you..  2 Peter 1.10.

  Paul says this to the Galatians--
  For you have been called to freedom, brethren, only do not turn your freedom into an opportunity for the flesh, but through love serve one another, Galatians 5.13.