Jesus sent out His disciples to heal the sick, cleanse the lepers, raise the dead, and cast out demons. This is in Matthew 10: 7 and then the last phrase of the same verse says, ‘freely you have received, freely give’. Further verses, verse 10, gives insight on the fact that the Christian messenger should not be focused on collecting cash on the preach journey but know that a worker is worthy of his food.
It is now common and sort of acceptable not to accept offerings only but to charge for doing works of service in the church. Unfortunately, Church is big business these days and a pastor who does not sell the gospel seems a lot stupid than following the instructions from God.
Christians should shun doing this for to them it is counted as sin.