What is the role of the Holy Spirit in conversion?

In 1 Thessalonians 1:5, Paul emphasizes that the gospel came not only in words but also in the Holy Spirit and with power. This highlights the Holy Spirit’s vital role in conversion, where He applies the truth of the gospel to the hearts of the dead in sin, bringing them to life through divine regeneration. This process, often referred to as 'irresistible grace,' assures believers that their faith is a gift from God, enabled by the Spirit's transforming work. Without the Holy Spirit's action, the human heart remains unable to respond to the gospel.