What does being in Christ mean regarding the Holy Spirit's sealing?
Being in Christ means the believer has been sealed by the Holy Spirit, and the Holy Spirit is in the believer. This is the reciprocal union: the believer is in Him, and He is in the believer. It is the secret tied to the Christ of resurrection power, seated at the Father's right hand.
Les explains that being in Christ is the secret. He points to Ephesians to show that if we are in Christ, we have been sealed by the Spirit. He also teaches that if we are in Christ, then the Holy Spirit is in us. This means the relationship is mutual: we are in Him, and He is in us. Les ties this to the Christ of the work of the cross, the Christ in resurrection power, the Christ seated in the heavenlies at the right hand of the Father, rather than to the earthly ministry of Jesus to Israel. He calls this mind-boggling.