If Jesus went to heaven when he died why did he tell Mary he hadn't yet ascended to his Father (John 20:17)?
If he didn't go to Paradise the day he died what are we to make of Luke 23:43 where he tells the robber that they would be together in Paradise that day? [But see.]
If the totality of a human ceases at biological death and bodily corruption begins immediately, then Jesus didn't go to Paradise (or Heaven if you think they're distinct) that day. He ceased to exist and his corpse, if he died as other humans died, began the process of corruption then and there. [If we hold that God miraculously preserved the corpse from corrupting we are faced with other questions and problems.]
Let's suppose (for argument's sake) that's it's true that a human doesn't cease to exist at biological death. I happen to believe that, but let's just pretend we knew without doubt that it's true. Let's say the human is a complex being and can suffer disembodiment—he can die without ceasing to exist. Death is the experience of the entire person and not just the body; what a person loses in dying is not existence but "embodied life"—the life God created humans for.
Suppose then that in losing embodied life (that is, in dying biologically) Jesus' "spirit" or "soul" went to his Holy Father. That would mean he "went to heaven". Why would we have difficulty believing that?
Well, there's John 20:17 where Jesus gently forbids Mary to continue to cling to him (using a present imperative). The reason he forbids her, he says, is because he hasn't ascended to his Father. Shelving for now why he said that to her, we know he had not yet ascended to his Father. Does that not show he couldn't have been with his Father previously—during his death experience, for example?
I'm sure it doesn't! His ascension to his Father (like the resurrection) is a distinctive part of the outworking of God's cosmic redemption. Though we don't need to say the word ascension here is used in a "technical" way (why would that trouble us?) Jesus' ascension is his departure from the world in glory to be exalted as Lord of All. The ascension completes the series of acts and experiences of Jesus by which God glorifies him. It is part of the triumphant (resurrected) Jesus' march to immortal glory.
His death experience, on the other hand, is Jesus being robbed—like every other human—of embodied life. As long as Jesus exists in that state, Death thwarts God's purpose for Jesus (and humanity). It wouldn't make any difference if Jesus' spirit or soul sat on his Holy Father's knee, he is in a disembodied state—he is experiencing death. It isn't just his corpse that lies in the tomb that has died—Jesus died. The spirit/soul doesn't experience death in the way the physical body does but the physical body is not all there is to a man—the entire person is robbed.
[For illustration purposes only: Imagine a person fully conscious of all that's going on, lying in bed for years with a body they can't use due to disease. To say the problem is confined to the body because the mind is fully functional would be unforgivable. To be created for and as embodied life and to have that gift thwarted affects the entire person.]
The upshot of all this is that Jesus' spirit being with his Father during the death experience (his sharing with us the judgment of God on sin) is nothing like the ascending to the Father of John 20:17. One is Jesus sharing judgment and the other is the resurrected Jesus going to glorious exaltation (compare 1 Timothy 3:16). Poor Mary was so glad to see him and Jesus is telling her she needs to understand thta it's not back to business as usual and that she will fully have him only when he goes to the Father (compare John 14—16).
So did Jesus go to heaven when he died? I do believe he did and because I believe that Paradise is simply another name for Heaven (stressing the blessedness of it) I'm sure Luke 23:43 teaches that. See 2 Corinthians 12:2, 4. I'm pretty sure that Jesus went to Heaven the day of his death for I'm certain he didn't mean the tomb when he said Paradise.
Is Paradise not a part of heaven, a sort of waiting place? I think we've come up with that notion mainly because we have difficulty with John 20:17. I think if we understand John 20:17 and Jesus' ascension as I've suggested above (or something like it) that we don't need that compartment notion. A brief word on Paradise.