1 Peter 1:13-
As Peter gives practical advice he constantly takes us back to the basics of the Christian gospel for the reason behind such behaviour. The salvation described so magnificently in the earlier section can and should result in men and women living as followers of Jesus no matter how difficult their circumstances may be.
44 For I am the LORD your God. Consecrate yourselves therefore, and be holy, for I am holy. You shall not defile yourselves with any swarming thing that crawls on the ground. 45 For I am the LORD who brought you up out of the land of Egypt to be your God. You shall therefore be holy, for I am holy.”
Holiness, Christlikeness, is urged upon God’s people for two reasons. It is our example (as his children we should reflect the family likeness) and it is our goal (when Jesus appears we shall be finally and fully like him; cf. 1 Jn. 3:2).