2 Corinthians 8:3-4
For I can testify that according to their ability, and even beyond their ability, of their own free will, too, they have given help.
2 Corinthians 8:12
For if there be first willing mind, the gift is accepted according to what a man has, and not according to what he has not.
2 Corinthians 8:17
For he not only consented to my request, but being thoroughly in earnest, comes to you of his own accord.
2 Corinthians 9:5
So I have thought that I must ask these brothers to visit you beforehand, and get your promised contribution ready in advance. I want it to be given of your bounty, not extorted from your covetousness.