you are the seal of my apostleship in the Lord

1 Corinthians 9:1-12
Paul defense his right to be an apostle.
Even though I may not be an apostle to others, surely I am to you! For you are the seal of my apostleship in the Lord.
Paul said it is not merely from a human point of view. It is written in the Law of Modes.
Paul said we sown spiritual seed among you, is it too much if they reap a material harvest from you? If others have this right of support from you, shouldn't we have it more?
Why?
Paul takes examples from his own life, to drive home the lesson that Christians should curtail their own freedom if there is any risk it will damage others or lead them astray.
If anyone has right, surely it is the apostle.
Seal: witness, approve it is true. By what he has done but not on what his said.
Paul tough those disciples and he himself did an example to let them know it is able to do it.
How?
I preach Gospel based on my behavior, I need more to explain it let people know the Lord, but not focus on me. And I need the power form the Lord. I can do nothing.