How do we know that God has called a preacher?

We understand that God calls a preacher based on the authenticity of his message and the response of the listeners. In the Gospel of John, it is stated that a man sent from God will have a message to preach, which aligns with the teachings of the apostles. This divine calling is recognized by the church when it witnesses the preacher’s fidelity in declaring the gospel and sees the fruits of belief manifest in the lives of those listening. Ultimately, the church only acknowledges what God has already initiated—true preaching is expected to resonate with faith and lead to belief. Thus, fulfilling God’s command to declare the glory of His salvation becomes a hallmark of a pastor's call.