Aaron and his four sons Nadab, Abihu, Eleazar and Ithamar were ordained and began their ministry as a priest. God's commands were very specific. They did what God command them to do until one day as you read the scripture, a tragic event happened to the two sons of Aaron. Nadab and Abihu were put to death by God because of their disobedience. At the end of chapter 10, it was mentioned that the remaining two sons of Aaron also disobey God, however they did not die. Now some of you who have not read the scripture, may ask why did God allowed the first 2 brothers die and the other 2 live where in fact all of them disobeyed Him. And why did God put the 2 to death immediately. I also ask myself the same question. After meditating the scripture, I researched and read the scripture all over again to understand what really happen.  What could be the cause: 1. Lack of reverence to God.  Lev. 10:3, it says,... Among those who approach me I will show myself holy; in the sight of all the people I will be honored.  They were greatly blessed by God, they are the sons of the High Priest, they were annointed, they were allowed to worship in the very presence of God but they did not show proper reverence to God. This was something God would not tolerate especially if you are someone who been so greatly blessed and is in a position to influence so many people. Leaders are to be example of those they lead. The lives of the people for which they are accountable are at stake.  2. They offered unauthorized fire.  God's instructions are very specific. But the two did not do exactly what was commanded to them.  3. They were drunk.  In Lev. 10:8-11 God told Moses to not drink wine or femented drink whenever they go to the Tent of the Meeting or else they will die. God mentioned this after the 2 sons of Aaron died.  Verse 10 its says that, you must distinguish between the holy and the common, between the unclean and the clean. Eleazar and Ithmar also disobeyed but were not put to death. The moment that their olders brothers die together with Aaron their father, God commanded them not to mourn but to continue their responsibility. Despite of what happen to their family, they choose to obey God even though their hearts are mourning. What did they not do?  They did not eat the goat in the sanctuary which were commanded to them. Moses was angry to them for not obeying and perhaps he was also worried that they might be put to death as well.  But God knew their hearts. It is not because they don't want to obey God but its because they couldn't bring themselves to eat when they were so overcome with sorrow and so they trusted that they served a gracious Father who would understand and show mercy to them.  I was reminded by this scripture: For I desire mercy, not sacrifice, and acknowledgment of God rather than burnt offerings. Hosea 6:6 NIV In this scriptures, I learned more of the character of God in that particular event that...  God is a just God and yet He is also a merciful Father.