Do we see a similarity between this passage and Romans 12:1-2: "Present your bodies a living sacrifice. . . . And do not be conformed to this world"? Paul is saying the same thing here, also mentioning the shunning of fornication, uncleanness, covetousness, filthiness, and other things, that is, sinful behaviors, how the world does things. The point is that we fulfill the showing forth of God's praises through being a godly example to the world. Showing forth God's praises involves our witness of how God lives.
But to do so requires sacrifice—putting human nature to death and overcoming indwelling sin. It is not easy. It requires disciplining ourselves, controlling ourselves, saying, "No!" to ourselves. On the other hand, it also requires us to say, "Yes, I need to do this good thing"—in service, in kindness, in mercy, in love. Either way—positively or negatively—we will have to sacrifice as a sacrifice is involved in almost any act of love.
If we conform to the ways of the world, how can we possibly show forth the praises of God? We would be just like the people of this world. Peter means that, in showing forth the praises of God, we must live contrary to the carnal ways of the world. The principle also includes the preaching of the gospel to the world, giving it a verbal representation of the praises of God through explaining His purpose.
Now, making acceptable sacrifices through Jesus Christ involves doing activities more frequently thought of as being "priestly." Such sacrifices include things like prayer (which we do privately) and study (which we also do on our own). When there is nothing else to distract us, we carve out private time with God's Word—come right before Him, into His presence. Making acceptable sacrifices also includes meditation, whenever and wherever. God tells Joshua in Joshua 1:8, "You shall meditate in [the Book of the Law] day and night." In Psalm 119:97, the psalmist says, "[The law] is my meditation all the day."
It includes praying about the multitude of subjects God reveals in His Word. It means praying for leaders in the church, both the faithful ones and those who have gone astray, at least for a time. It also includes the activities that Paul mentions in Hebrews 13:15-16: offering "the sacrifice of praise to God" and doing good works and sharing our blessings. Jesus advises in Matthew 6:3 that in doing such things, we should not let our right hand know what our left hand is doing. Most of these deeds are things that we are to do privately.
John W. Ritenbaugh
New Covenant Priesthood (Part One)