How do we know pastors should be supported?

Paul elucidates in 1 Corinthians 9 that it is ordained by the Lord that those who preach the gospel should live by the gospel. He presents several reasons for this, including the fact that apostles were given authority by Christ to minister without the burden of secular employment. This establishes a biblical principle that pastors are entitled to support from the congregation. The recognition of preachers as God's gifts to the church reinforces the obligation to provide for them, which ultimately honors Christ.