Bible Verses About Steadfastness: In striving for the faith of the gospel

Only let your way of life be worthy of the Good News of Messiah, that, whether I come and see you or am absent, I may hear of your state, that you stand firm in one spirit, with one soul striving for the faith of the Good News;

Beloved, while I was very eager to write to you about our common salvation, I was constrained to write to you exhorting you to contend earnestly for the faith which was once for all delivered to the holy ones.