Because God has revealed his saving work in Christ, we must hold fast to the word of life and shine as lights in the midst of the world God loves.

Philippians 2:12–18 (ESV): 12 Therefore, my beloved, as you have always obeyed, so now, not only as in my presence but much more in my absence, work out your own salvation with fear and trembling, 13 for it is God who works in you, both to will and to work for his good pleasure.
14 Do all things without grumbling or disputing, 15 that you may be blameless and innocent, children of God without blemish in the midst of a crooked and twisted generation, among whom you shine as lights in the world, 16 holding fast to the word of life, so that in the day of Christ I may be proud that I did not run in vain or labor in vain. 17 Even if I am to be poured out as a drink offering upon the sacrificial offering of your faith, I am glad and rejoice with you all. 18 Likewise you also should be glad and rejoice with me.