Phil. 1:6 Does NOT
Support Eternal Security
Phil. 1:6 is actually the last part of a sentence which starts at v. 4:
(1:4) In all my prayers for all of you, I always pray with joy (1:5) because of your partnership in the gospel from the first day until now, (1:6) being confident of this, that he who began a good work in you will carry it on to completion until the day of Christ Jesus. (1:7) It is right for me to feel this way about all of you, since I have you in my heart; for whether I am in chains or defending and confirming the gospel, all of you share in God’s grace with me (NIV).
By going back to verses 4 and 5, it becomes apparent that the good work in v. 6 refers back to their partnership in the gospel (v. 5). In other words, the church at Philippi was partnered with Paul through their financial donations and, therefore, shared in his fruit. See also 4:14-18. That was the good work which had begun in them and which Paul was confident God would carry on to completion—their partnership in the gospel.
Furthermore, verse 7 goes on to state that it was right for Paul to feel so confident about this because he (Paul) had them in his heart, meaning he would pray for them. When one examines the context of Phil. 1:6 it becomes clear that it cannot be correctly used to support once saved always saved (OSAS). Only people with a preconceived idea about this verse or who never considered the context will think it supports OSAS.