Matthew 12:40
12:40 For just as Jonah was in the belly of the huge fish for three days and three nights, so the Son of Man will be in the heart of the earth for three days and three nights.
Matthew 18:6
18:6 “But if anyone causes one of these little ones who believe in me to sin, it would be better for him to have a huge millstone hung around his neck and to be drowned in the open sea.