...so that in the coming ages he might show the immeasurable riches of his grace in kindness toward us in Christ Jesus.
This is why Christians are saved by the death and resurrection of Christ. The incredible grace offered in our salvation is not just a one time experience. God saves us so that forever the riches of His grace might by showered on us. God loves sinners. God saves repentant sinners... forever.
God desires to bless us through the grace of His Son for all eternity. That's quite an offer of generous grace to one sinner. But this scripture says this grace is offered to all who will put their faith in the grace offered in Jesus (see verse 8 for clarification). It is multiplied exponentially then by every person who trusts Christ for salvation. Each Christian knows the wild, generous riches of God's grace in kindness in Christ Jesus!
Truly it is amazing grace that saved a wretch like me! I am forever more now showered in the riches of Your great grace and love. I am always blessed because You have saved me.