in Christ (v.1) — available because of our union with Him
comfort of love (v.1) — the tender, joyful effect of love — love as an incentive to action
fellowship of the Spirit (v.1) — because believers share the Spirit and His ministry, they have a motive for unity, sympathy and love
In view of the fact that there is a certain ground of appeal in Christ which exhorts, since there is a certain tender persuasion that comes from divine love, in view of the fact that there is a certain joint-participation with the Spirit in a common interest and activity, since there are certain tenderheartednesses and compassionate yearnings and actions … — Wuest, pages 58-59
affection (v.1) — inward feelings, compassions — the outward expression of those feelings
fulfill my joy (v.2) — Paul already (1:4) expressed his joy at their faith, but he wants them to complete it decisively and wholeheartedly. He then goes on, through verse 5, to explain how they can do this.
being like-minded (v.2) — think the same thing, be of the same mind
one accord (v.2) = fellow-souled — unity in thought, purpose, heart and mind
one mind (v.2) — an intensification of “be like-minded” — minding the one thing — not opinion but moral refection
Paul had nothing corrective to say about the Philippians’ doctrine, but he had heard that they had squabblings and disunity and was addressing that issue by exhorting them to have common interests — the same love, the same sentiment, the same mind