The Corinthian Church had promised to help brethren in Palestine, and the Corinthians were giving every first day of the week to save up money for it so that when Paul arrived, they could give him the money.
Paul reminded them,
“Therefore I thought it necessary to exhort the brethren to go to you ahead of time, and prepare your generous gift beforehand, which you had previously promised, that it may be ready as a matter of generosity and not as a grudging obligation” (2 Corinthians 9:5).
He did not want them to give because they felt like they had to give it, but he wanted them to do it because they wanted to do it.
Why do you give every first day of the week?