Philippians 2:12 - 13
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.
For follow-up discussion and general commentary on the topic. Comments are sorted chronologically.