C.S. Lewis pursued theology/spirituality deeply and sincerely. After the death of his wife he wrote a fairly brief contemplative emotional and spiritual journey of his grief, “A Grief Observed”, which helped him ( and many of his readers) cope with the impact of the occasion. He wrote several other meditations as well.

I read and reread Go Ask Alice when I was 12 or 13 (I’m in my 60s now, what a trip🤣) and I loved it and wanted to believe in it and I did for a while, but a couple of years later (like 30 maybe😅) I got curious and reread it and I was damn near horrified. It did not ring true at all. It made me angry. It was wooden and fake as hell. Drat!

Heartily agree “a children’s book with adult ideas”. WitW is also one of my comfort books, as are those in the NARNIA series. Wrinkle in Time, ohhhhh.