Which Christ are we attached to as believers — the earthly Jesus or the ascended Christ?

Believers are attached to the ascended Christ, the Christ after His death, burial, and resurrection, now in glory—not the Christ known after the flesh in His earthly ministry. Paul says we know no man after the flesh; the pre-cross Jesus was not the object of salvation that the post-cross Christ is.

Les explains that because of the work of the cross—His death, burial, and resurrection—henceforth we know no man after the flesh. Many preach about Jesus in His earthly ministry, His miracles, signs, and wonders, but Paul says we are not following any man in the flesh. We are to take Christ after the work of the cross, after His death, burial, and resurrection, now ascended in the glory. That is the Christ to whom believers are attached. It is the same man and the same God, yet the Christ before the cross was not the object of our salvation that He is after the cross, because the work of the cross makes possible our salvation experience. Paul lived contemporary with Christ after the flesh, but now, from His death, burial, and resurrection onward, we do not look back and know Him in His earthly ministry as such.

2 Corinthians 5:16

Wherefore henceforth know we no man after the flesh: yea, though we have known Christ after the flesh, yet now henceforth know we him no more.

Which Christ are believers attached to—Jesus in His earthly ministry or Christ after the cross?

Believers are attached to Christ after the work of the cross—after His death, burial, and resurrection, now ascended in glory—not to Jesus in His earthly ministry. The Christ before the cross was not the object of our salvation that He is after the cross, because the cross makes salvation possible.