This is based on Philippians 2:12-13 which says, “So then, my beloved, even as you have always obeyed, not as in my presence only but now much rather in my absence, work out your own salvation with fear and trembling; For it is God who operates in you both the willing and the working for His good pleasure.” This is not referring to redemption from sins which Christ accomplished on the cross and which we receive by faith. This refers to a practical salvation in our daily life. When we humble ourselves before God as Christ did (verses 5 - 8), then God operates in us both the willing and the working for His good pleasure. Our “work” is to humbly accept whatever situations God has arranged for us. This opens the way for God to do His work in and through us.