I ask the reader to decide for oneself which interpretation is correct. “But we are bound to give thanks to God always for you, brethren beloved by the Lord, because God from the beginning chose you for salvation through sanctification by the Spirit and belief in the truth, to which He called you by our gospel, for the obtaining of the glory of our Lord Jesus Christ.” (NKJV) Interpretation # 1: Paul is thanking the Thessalonians for what they did that caused God to love them and choose [elect] them for salvation. God’s choice was made due to His foreknowledge of their choosing Christ when the Gospel was preached to them. They first believed the truth of the Gospel, after which God then sent His Spirit to regenerate them. They will attain heavenly glory if they allow the Spirit to continue to sanctify them during their lifetime. Paul wrote this that they might know the truth as to how they became Christians and how they might stay Christians. In other words, they have every right to share the glory of their salvation with the Lord. Interpretation # 2: Paul is thanking God, not the Thessalonians, for their election to salvation. He understands that the idolatrous, pagan Thessalonians did not come to faith due to their own efforts, whether good use of ‘free will,’ or a disposition toward holiness. Rather, he understands they were living in absolute spiritual darkness, worshipping devils, not seeking the true God. But God, in eternity, out of love, decided, purposed, decreed to have mercy upon them, knowing that they, as sinners fallen in Adam, would neither seek nor desire Him. So God predestined them to salvation before they were born, before they could attempt to merit salvation (which they would not and could not). This He did first through the means of calling by the Gospel of Jesus Christ. Paul acknowledges their calling consisted not only in the preaching of the Word, but in the sanctifying, regenerating power of the Spirit who effectively gave them the gracious gift of faith by which they believed the truth. Thus, through the sanctifying power of the Spirit which cannot fail, they will continue in saving faith until they are united with Christ in glory. Paul wrote this that they might know the truth as to how they became Christians as well as how they will stay Christians. In other words, all the glory belongs to God alone.