1 Peter 2:9-12

But you are a chosen race, a royal priesthood, a holy nation, a people for his own possession… Once you were not a people, but now you are God's people; once you had not received mercy, but now you have received mercy. Beloved, I urge you as sojourners and exiles to abstain from the passions of the flesh, which wage war against your soul. Keep your conduct among the Gentiles honorable, so that when they speak against you as evildoers, they may see your good deeds and glorify God on the day of visitation.

When God calls His people a “kingdom of priests,” He highlights that they are to stand in a mediate, middle position between Him and people. As His priests, they are to represent God to the world, and the world to God. As priests, we are called to live, serve and sacrifice, to be effective in our mediatorial role. Christ intervenes for us in our priesthood, helping us to pray for the world and to witness to it.

At Mount Sinai, God told the Israelites, “If you will indeed obey my voice and keep my covenant, you shall be my treasured possession among all people, for all the earth is mine, and you shall be to me a kingdom of priests and a holy nation” (Exodus 19:5-6, emphasis mine). Unfortunately, Israel failed again and again to fulfill this special role to which God had called them.
 
They offered their sacrifices of bulls and goats, but their hearts and lives were often far from the Lord; they were not “doing justice, loving kindness, and walking humbly with their God” (Micah 6:8). Fortunately for us, God sent His Son into the flesh, a human being, to atone for our sins. Christ was Israel reduced to one – who, as our great high priest, offered the perfect and necessary sacrifice. His sacrifice was a life in keeping with God’s will, from its beginning all the way to the cross. At the cross, He gave Himself as God’s Lamb, without blemish or spot, for the world’s sin. As a result, God no longer needs the sacrifice of animals.

David says, “The sacrifices of God are a broken spirit.” (Psalm 51:17) In His grace and mercy, God forgives our sins for Christ’s sake. He transforms us from being no one special to being God’s people, from being without mercy, to having received mercy.
And he calls us to present our bodies as living sacrifices, holy and acceptable to God. This is our reasonable act of service (Romans 12:1-2).

Dedicating ourselves to God’s purposes in the world is the fitting sacrifice God asks of us. By living in His will, we will not only do what is right; we will be exposed to the needs of the people God is sending us to serve. We will learn their joys and sorrows, their fears and failures, their struggles and successes, their ups and downs. Holding up God’s love and will to their situation and needs will help us discern how to respond with wisdom and love. Being in tune with God can also very well instruct us how to carry out our other priestly roles: praying and witnessing. By knowing others’ needs, we can approach God’s throne of grace with our intercessions for them, and reach out to them with genuine care, rather than preconceived notions which may frustrate rather than help.

Being God’s kingdom of priests means that our life on earth should be governed by our heavenly citizenship. As Peter writes, we are sojourners and exiles here. Rather than having the way of the world and our sinful nature guide our thinking and doing, let us conform our conduct to the fact that God has claimed and purchased us to be His people!
Let us reject greed and slander and embrace contentment and talk that builds up. Instead of selfishness let there be generosity; rather than seeking to control, let us show compassion. Because we priests have been freed from self-centered thinking and acting by the sacrifice of our Lord, let us offer ourselves as living sacrifices to benefit and bless others.

Our place in life can be most helpful for realizing where our priestly service should be offered. Let us start at home, with husbands and wives listening and responding to each other in love. Let parents seek to raise their children as God’s children. Moving out into the neighborhood, let our relationships be marked by patience and concern, honesty, and integrity. Those same qualities can characterize our priestly service in the workplace and in society in general. There is no end of opportunities for serving and sacrificing as God’s priests, seeking to represent our Lord’s values and love in the world.

If the church is going to practice its identity as God’s kingdom of priests, let us encourage each member to participate. We can encourage others to use the gifts and personalities God has given them, for the good of the greater Church. We are a single body. Rescued by God’s mercy in Jesus Christ, let our relations within the church be marked by truthfulness and sensitivity, compassion for and commitment to one another. Just as old Israel often failed to match its conduct with its God-given identity, we too fail. We also need forgiveness to restore and grace to renew us. By such inner workings within the priesthood, we will be equipped, energized, and empowered for our life in the world.

By having our lives fashioned by God’s choosing us to be His priestly kingdom, His mediators, and using our God-given gifts, we will be better able to represent God to the world. Our transformed lives will lend credibility to our witness, and the invitation to our fellowship will be warmer and more welcoming.