Having appealed to the church at Corinth to have their collection of funds ready to be collected and then distributed, Paul asks the church to be ready to give when they come. The church had promised to give a particular amount, and Paul wants to make sure that the transaction feels like the joy-filled, generous, gift-giving that it is, rather than some kind of extortion to be handed over begrudgingly. He encourages them to give by using a parallel, comparing their giving to the sowing of seeds, and seeds, as we all know, start small but produce something larger and more fruitful. That fruit includes the glory of God amongst his people, and deeper unity and affection for each other.