What does 1 Thessalonians 3:12 mean?

Paul's prayer in these verses expresses his strong desire that the Lord would keep on increasing the Thessalonians' love. He uses a term derived from the Greek root word perisseuo, which implies something that "overflows" or "spills over the top." Paul desires to see their love greatly increase for fellow believers and everyone else. Paul's love for the Thessalonians served as a model for the believers at Thessalonica. In 1 Corinthians 13:13 Paul named love as the greatest quality of the Christian life, In 1 John 3:14 the apostle John cites love as a proof of one's salvation, and in 1 John 4:7 he writes, "Beloved, let us love one another, for love is from God, and whoever loves has been born of God and knows God."

Christians should love one another and also love the lost. Jesus, the Good Shepherd, demonstrated love for the lost. He illustrated this love by telling a story about a shepherd who left his ninety-nine sheep to rescue one lost sheep. When he brought it safely to the fold, he called his neighbors to rejoice with him (Luke 15:1–7).