Who me, a Priest?

Read Leviticus 8-10.

God sovereignly selected the tribe of Levi to serve as priests.  Those who served as priests did so by birth.  They were charged with the administration of the sacrifices and offerings, and the maintenance in and around the Tabernacle for the nation.  Aaron, Moses' brother, being the patriarch, became the first chief priest.  The ordination and installation of the priesthood was one of the most elaborate rituals of all.  The detailed instructions of how to perform their duties had been given to them with exactness from God.

But like Satan's original temptation in the Garden of Eden, sin begins with questioning what God said.  How many have declared, "It is my life and I will do what I want" to their own self-destruction?  Nadab and Abihu, Aaron's own sons, decided that they did not have to follow God's word.  They showed up for service and went through the motions of worship, but their hearts and behaviors were rebellious and disobedient.  God's judgment in this case was swift.

These were Moses' nephews.  It had to be emotionally painful and publicly embarrassing.  Yet, his priority commitment was to God and His word.  To his silent brother, Moses said, "This is what the LORD has said, 'Among those who are near me I will be sanctified, and before all the people I will be glorified.'" (10:3)  One way or another, through faithful living or swift judgment, God will protect His word and His glory.

As a follower of Jesus, you are a priest.
Today, under the New Covenant, people become priests of God by the second birth.  "As you come to him, a living stone rejected by men but in the sight of God chosen and precious, you yourselves like living stones are built up as a spiritual house, to be a holy priesthood, to offer spiritual sacrifices acceptable to God through Jesus Christ." (1Peter 2:4-5) 

As a priest, you have a job to do for God.
The instructions have been given to us as to how to live out God's expectations in serving Him.  The Bible is God manual of how to live.

As a servant of God, you must be live to please Him. 
Our service to God is to be done in humility, submission and carefulness.  You won't be perfect, but you must be vigilant about your thoughts, words and actions.  We do not live for ourselves but for the One who sent us to serve.