Since in the quote, words such as crush, cut, and singe are used, which are words that show some force being used, the denotation of the word "cast" in this excerpt is similar - B. throw with force. God doesn't just toss these sinners to hell - he makes sure they never come back.
According to the dictionary the word "cast" can be used to indicate the action of throwing, throwing, throwing, throwing. In this case, using the word do not know denotative meaning the phrase would read "Thus, it is easy for God when he wishes to throw his enemies to hell."