How does a sinner come to call upon the Lord?

According to Romans 10:14-15, a sinner cannot call upon the Lord without first believing in Him, and they cannot believe without hearing about Him. This emphasizes the role of preaching in the work of salvation; God sends preachers to proclaim the gospel, and through the faithful preaching of God's Word, the Holy Spirit works in the hearts of the hearers. Hence, the call of the sinner is a response to the gospel message, revealing the grace of God at work. A sinner is given a new heart that longs for God, enabling them to call upon Him in faith.