1 Corinthians 3:5-6 Who then is Paul, and who is Apollos, but ministers by whom ye believed, even as the Lord gave to every man? I have planted, Apollos watered; but God gave the increase.
Paul planted, but Paul didn't cause the plants to grow.
Apollos watered, but Apollos didn't cause the plants to grow.
God caused the plants to grow! He is the one who gives the increase.
But before the increase can take place, there need to be an opportunity for growth.
For example: Watering a plant without sunlight and without the right soil conditions will cause the plant to die. Before an increase can take place, there needs to be an opportunity for growth.
Paul planted, and Apollos watered, but none of them were able to create the opportunity to plant.
Not only does God give the increase. But since God created the soil and sunlight. He's the one that creates the opportunity for growth.
Both Paul and Apollos were ministers. But it was God who gave them the opportunity to minister.
If we start with thanking God for giving us the opportunity to minister, it'll be a lot easier to thank God when He gives the increase.