'Firm' in the Bible

Only [be sure to] lead your lives in a manner [that will be] worthy of the gospel of Christ, so that whether I do come and see you or remain absent, I will hear about you that you are standing firm in one spirit [and one purpose], with one mind striving side by side [as if in combat] for the faith of the gospel.

Therefore, my fellow believers, whom I love and long for, my delight and crown [my wreath of victory], in this way stand firm in the Lord, my beloved.