Be obedient to God, and do not allow your lives to be shaped by those desires you had when you were still ignorant. Instead, be holy in all that you do, just as God who called you is holy. The scripture says, "Be holy because I am holy."
(1 Peter 1:14-16 GNB)
In 1 Peter ,Apostle peter taught his fellow Jewish believers (vs 1,18)
To be Holy quoting from the only scriptures/God’s word at that point of time The Torah from book of Leviticus
Ch 11—Dietary Law
Ch 19—Sabbath and instruction to daily practices and behaviour
Ch 20—keep my statutes
Is the only way to be Holy as YHWH is Holy
"Speak to all the congregation of the people of Israel and say to them,
You shall be holy, for I the LORD your God am holy.
Every one of you shall revere his mother and his father, and you shall keep my Sabbaths: I am the LORD your God. …...
And you shall observe all my statutes and all my rules, and do them: I am YHWH ." (Leviticus 19:2-3,37 ESV)
Consecrate yourselves, therefore, and be holy, for I am YHWH your God. Keep my statutes and do them; I am YHWH who sanctifies you.
(Leviticus 20:7-8 ESV)
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.
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." This is the law about beast and bird and every living creature that moves through the waters and every creature that swarms on the ground, to make a distinction between the unclean and the clean and between the living creature that may be eaten and the living creature that may not be eaten.
(Leviticus 11:44-47 ESV)