2 Corinthians 8:6-8

Insomuch that we exhorted Titus, that as he had made a beginning before, so he would also complete in you this grace also. But as ye abound in everything, in faith, and utterance, and knowledge, and in all earnestness, and in your love to us, see that ye abound in this grace also. I speak not by way of commandment, but as proving through the earnestness of others the sincerity also of your love.