How does the gospel act as a hammer in soul-winning?

In the context of soul-winning, C.H. Spurgeon illustrates the gospel's impact as akin to a hammer that shatters hard-heartedness and resistance to God's truth. Just as a hammer strikes repeatedly against rock until it eventually breaks apart, the consistent proclamation of the gospel persists in affecting hearts, even when initial responses seem negative. Spurgeon emphasizes that each strike—each presentation of the gospel—contributes to a process of change, ultimately leading to moments of breakthrough where individuals come to faith. This illustrates the persistence required in evangelism and the trust that ultimately, God's word will perform its intended purpose in due time (Isaiah 55:11).