BTW I don't know anything about Fransis of Assisi, but the passage you reference, Jesus is speaking to his apostles as he sends them out to spread the gospel. I beleive he is telling them and us that it is our repsonsiblity to support our pastors. Where your money is there will your heart be. (Not exact quote) It is a way for them to know who responded to the message and who didn't.
Becky