Paul has just finished emphasizing the importance of loving the truth. In fact, he has clearly stated that judgment waits those who do not (2:12). Paul, now begins to praise the Thessalonians. They are God’s beloved, of whom Paul is thankful (2:13).
Paul is thankful for them because “God has chosen them”. Chosen is modified by important phrases that help us understand what being “chosen” means.
1. Chosen to salvation. God saves whom He chooses. Those chosen by God are chosen for salvation. Unlike the ones who are condemned for their “lack of belief in truth”, and “pleasure in unrighteousness”, those chosen receive salvation.
2. Chosen by sanctification of the Spirit and by belief in the truth. Although, some religious groups and leaders see God’s choice as arbitrary, Paul argues differently. Paul states that the agency by which we are chosen is the sanctification of the Spirit and belief in the truth. Those who are chosen are those who trust in the truth and are set-apart by the Spirit. When individuals trust (which in Paul’s definition of belief would include obedience) in the truth, then they are chosen by God.
The choosing of God is preceded by the calling of God. God calls to the world and those who accept that call are chosen. Once again Paul explains “how” God calls. God calls through the gospel. The message of Jesus, God in the flesh, living, dying, and resurrecting to pay for our sins and provide us with justification, is how all men are called.
Working backwards for a moment, a clear picture emerges. God calls mankind by the gospel (2:14). Those who believe in the truth of that message (2:13) and are thus sanctified by the Spirit (2:13), are chosen by God for salvation. Paul does not teach an arbitrary choosing by God to save some and condemn others. Instead God calls through the gospel and those who believe the gospel* are chosen for salvation.
How, then, should we respond to God’s choosing us? Paul continues in verse 15 with an explanation. We respond by “holding fast to the traditions.” These traditions were taught by word, or by epistle. Tradition here refers to the teaching of the Apostles and Prophets who were given the privilege by God to share with us Divine Truth. We “hold fast” these truths. The church has no right to “let go” or change Divine Truth. We let go of error (2:2), but not Truth.
The conclusion of the section is a pray of comfort and establishment. The Thessalonians are facing persecution because of God’s choice of them. They need comfort. In the same way, they need to continue to be established in word and work. Our Lord Jesus Christ, and God our Father, can accomplish both.
*Paul does not use belief as many in the religious world do today. It is not simply mental assent, instead it is trustful obedience. Genuine belief without obedience is foreign to Paul. The obedience God requires is seen in numerous New Testament passages such as Matthew 28:18-20, Mark 16:15, 16, Acts 2:38, Romans 10:9, 10.