Parenting- sometimes it feels like mission impossible

WC often picks bedtime to hit me with his theological/philosophical questions. While brushing his teeth they come out of blue like a guided missile targeted to leave me stumbling for answers that will satisfy him and not lead to another question. This is mission impossible parenting. Why he chooses this time of day to ask- stalling bedtime or simply this is when these issues cross his little mind while getting ready to settle in for the night, I don’t know. Answers aren’t always easy for me to understand, as the adult. How do I explain these things to him? If there are any discrepancies in my answers this child picks it up- a cop with a radar gun sitting on the side of a long stretch of road where the speed limit lowers by 10, he’ll stop me in a heartbeat. Tuesday evening conversation went something like this:
“Mom, did God really make us?”
“Yes.”
“Before He made people, was God alone…was Jesus there?”
“Yes.” (sly answer there.)
“How long did Jesus live on earth?”
“They think about 33 years. A long time ago.”
“Why did Jesus die on the cross?”
(oh crap) “Um…as payment for our sins…so we can go to heaven.”
He looks concerned about that last part. We’ve already had many discussions on heaven and he doesn’t want to go there because he doesn’t know where it is. And he often uses the phrase that he doesn’t remember what God looks like. Which these ponderings began after my Grandfather passed away. Initially we didn’t tell WC about it figuring at 3 he wouldn’t remember him. But last year he began asking why he hadn’t seen Granddad in a long time & we finally told him that Granddad had gone to heaven. And ever since then, out of the blue, he expresses fear of growing old and dying. One day he was afraid that his father & I would die then he & CJ would be alone in the house. The only thing I could think to do was assure him that he & CJ would never be alone. I can’t promise him the other- it isn’t up to me. But I don’t mention that either.
Then as quickly as the theological discussion started it was over:
“Are we made of meat?”
“Yes.”
“Nu uh.”
“Yes. Muscle is what meat is.”
“We don’t eat people.”
“No. the meat you eat is the muscle from cows or pigs.”
“Pigs...like roast?”
“Or ham, bacon, hot dogs.”
“Yummy…hot dogs.” And with that he skipped out of the bathroom to find Jay to tuck him into bed.
I informed Jay he was going to start supervising the nightly teeth brushing and potty time so he could get the thrill of answering these questions. Not that he’s any better equipped than I am. I feel so inadequate to answer these types of questions. Do other children ask their parents these sorts of questions? When I envisioned raising my son it never occurred to me that I would need to have answers to these sorts’ conundrums.