Philippians 1:27
Only let your conversation be as it becomes the gospel of Christ: that whether I come and see you, or else be absent, I may hear of your affairs, that you stand fast in one spirit, with one mind striving together for the faith of the gospel;
Torrey's Topical Textbook—AKJV

Jude 1:3
Beloved, when I gave all diligence to write to you of the common salvation, it was needful for me to write to you, and exhort you that you should earnestly contend for the faith which was once delivered to the saints.
Torrey's Topical Textbook—AKJV