"my chest is in my head" gives me the image of his head hanging down and touching his chest (on the cross).
"lets go down together" also gives me the image of him telling the thieves on both sides of him (who symbolize humankind - the ones who reject him, like the one thief, and the ones who accept him, like the other)... he tells them, "lets go down together", which could be seen as, "i go down with you in your fallenness, i'll pay for it", or "i feel your pain, son".
"my chest is in my head" gives me the image of his head hanging down and touching his chest (on the cross).
"lets go down together" also gives me the image of him telling the thieves on both sides of him (who symbolize humankind - the ones who reject him, like the one thief, and the ones who accept him, like the other)... he tells them, "lets go down together", which could be seen as, "i go down with you in your fallenness, i'll pay for it", or "i feel your pain, son".