My Hope for Mercy: Christ Became a Servant

"For I tell you that Christ became a servant to the circumcised to show God's truthfulness, in order to confirm the promises given to the patriarchs, and in order that the Gentiles might glorify God for his mercy." -Rom 15:8-9

Christ became a servant to the circumcised to show God's truthfulness for two reasons:
-in order to confirm the promises given to the patriarchs, and
-in order that the Gentiles might glorify God for his mercy.

A question rises in my mind as i read these verses:
How does Jesus becoming a servant to the Jews (the circumcised) cause Gentiles to glorify God for his mercy?

Trusted promises as the foundation to glorify God for his mercy
The reason Gentiles would glorify God has its foundations in the confirmation of the promises given to the patriarchs. By becoming a servant to the Jews, even unto death, Jesus confirms God's faithfulness to His promises given in the Old Testament. If God is seen to be faithful to His OT promises, then those promises given to the gentiles can be trusted (or hoped in-v.13). And Paul gives 4 examples of OT promises that show Gentiles are included as God's people.

Jesus as the foundation for trusted promises
If the reason that gentiles can trust the promises of God include them is because God is faithful, how can we know God is faithful?
"Christ became a servant to the circumcised to show God's truthfulness." God's faithfulness to His promises is confirmed in Jesus' becoming a servant.

O how precious the truth of God's faithfulness proved in the life of Jesus! It is my hope and peace!