For Christians today, we are all fully under the blood of Jesus. Without it, we have zero protection from God's wrath. With it, we are fully protected from it. However, the same temptation exists today for all Christians that existed for Nadab and Abihu. That is, the tendency to take God for granted or to allow our arrogance to move us away from how God expects us to live in this life. It is a constant battle for the Christian, isn't it? Thank God He does not deal with us as He dealt with the Israelites under the Law!