How do we know a minister is called by God?

A minister's validation comes from the work of Christ in the hearts of the congregation, as expressed in 2 Corinthians 3:2-3. Paul indicates that the people themselves are the proof of his ministry, as they are an epistle known and read by all men, written not with ink but by the Spirit of God. This transformative work in believers signifies that the minister is indeed sent and utilized by God to proclaim the gospel. It is the inward change in the believer—receiving the Word with joy, turning from idols, and growing in faith—that serves as evidence of a true minister’s calling.