God who makes both us and you stand firm in Christ

2 Corinthians 1:12-24
Now this is our boast: Our conscience testifies that we have conducted ourselves in the world, and especially in our relations with you, with integrity and godly sincerity. We have done so, relying not on worldly wisdom but on God’s grace.
For no matter how many promises God has made, they are “Yes” in Christ. And so through him the “Amen” is spoken by us to the glory of God. 
Now it is God who makes both us and you stand firm in Christ. He anointed us,
Not that we lord it over your faith, but we work with you for your joy, because it is by faith you stand firm.  
Why?
In his first letter Paul promise to come to Corinth via Macedonia. Later he decide to make two visits, on the way to and from Macedonia. In the event he has done neither, and the Corinthians have criticized hi for shilly-shallying. But this is not the reason for the changes of plan. He took his decision because of the state of affairs in the church. Having had one head-on clash, he wanted to delay visiting them again until relations were happier. So he tried to sort things out by letter - a letter he feared would hurt them, and which was painful to write.
Joy is the symbol of Christian, faith brings joy, joy makes life to the glory of God.
Amen is spoken by us to the glory of the Lord! We agree what have done by the Lord!
How?
Give glory to the Lord, who makes us stand firm in Christ.