What is union with Christ? And how does this union help us advance in personal holiness?

We asked J. I. Packer recently, and he answered in this rich 9-minute video:

Transcribed Excerpt

“[As a Christian] you have to face a great deal of opposition from the world, the flesh, and the devil. But as the new creatures that you are in Christ — risen with him, with the power of his resurrection mediated through the Holy Spirit into the actual living of your life — you can stand fast. You pray for power to stand fast. You set yourself to stand fast. And you find that you are standing fast. In his strength you can do it. And this is one of the secrets of sanctification, the secret which I would say matches, balances, and complements what we were saying earlier on about mortification (draining life out of sinful desires, urges, and lusts). . . . [Union with Christ] is the basic relationship from which flows the gift of the Spirit who indwells you and through which, via the Spirit, comes the power to model your life behaviorally on Christ.”

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