I may die, tonight. (“I lay me down, my soul to keep.”) Haven’t finished Christian snake book.
But essentially Moses is purported to have said “rise like these snakes” to the Israelites when they were in slavery.
Jesus is purported to say “from the earth, you rise like the snake and I am exalted on the cross to take your sins for your salvation and eternal life, and take you “further” to Heaven.
These snakes, or copper snakes (because copper and snake is similarly spelled) raise the Israelites from slavery, and metaphorically raises the Christian believer, thus saved, to life eternal.