"Wherefore gird up the loins of your mind, be sober, and hope to the end for the grace that is to be brought unto you at the revelation of Jesus Christ; As obedient children, not fashioning yourselves according to the former lusts in your ignorance: but as He which hath called you is holy, so be ye holy in all manner of conversation (lifestyle); Because it is written, be ye holy for I am holy." 1 Peter 1:13-16
This might seem like an impossible task, but it is not. Be ye holy is instruction to set your eyes on Christ and rely solely on the work that Christ has done to purify you. Through the sanctification by the Word of God you can be holy.
Now if you are thinking that being holy is doing everything perfectly you are mistaken.
If you are thinking that being holy means that you won't ever make a wrong decision, you do not understand the Word of God.
If you are thinking that being holy means that you have to be a member of a holiness church you are not thinking wisely.
To be holy is to follow after Christ, acknowledging your frailty, your insufficiency, your inability, your inadequacy; acknowledging what you are able to do and moving forward with your skills and talents to serve the Lord, but also acknowledging what you cannot do without the hand of the Lord and asking God to accomplish in you what you cannot do. No one is holy apart from Christ. That's right! So-called holy men who claim to be holy, that believe in other gods and do not accept Christ as their Saviour, are not holy. They are religious. You cannot be holy without the indwelling Holy Spirit living within the inner man.
The instruction to be holy comes with good advise:
Gird up the loins of your mind (God-thinking)
Hope to the end of your physical life
Be obedient with the knowledge that you already possess
Rebuilding your life/lifestyle with godly attributes, not turning back to your old ways
You were called to holiness living
Live holy in Christ
One of the arguments against holy living is that only God is holy, how then can we be holy like God? Great question. You can't. When God says 'be ye holy as I am holy', God is speaking to your spirit. "God is a Spirit (John 4:24) and he that worships Him must worship Him in spirit and truth." If you were to trust your inner man, you would live differently. If you were to trust your inner man, you would recognize the godly thing and choose it. If you were to trust the inner man you would realize that God does not call us to anything that we cannot accomplish. You would also realize that you cannot accomplish being holy without allowing God to live in you and through you.
Also to be holy as a man is not meant to assume that we can be holy like God is holy. Every attribute of God is perfect and flawless. When God speaks to us of our faith, belief, holiness, sanctification, power, strength, courage, hope, etc., each of these are to be seen as they were designed to be according to what was created.
God is omnipotent (unlimited power), we have limitations to our power
God is omniscient (all knowing), we were designed with limited ability for knowledge
God is omnipresent (all places at one time), we can only be at one place at one time
God is love, we love
The same with God is Holy. We are holy with Christ in us, because of Christ, not because of something we can do or something we can be or something we can accomplish. We can be holy because Christ lives in us. Now this is where I lose many people.
You cannot help but be holy because Christ is in you.
I know that you don't feel holy all the time. I also know that you don't always make the right decisions or choose wisely in every instance, but that is not what constitutes holiness. Holiness is imputed on the believer, not earned, nor is it accumulated after many years of faithful service. That kind of holiness is good works and good works are beautiful proof that God is in you working His will. But holiness is installed in you by faith. God designed you to be holy, because He is holy, and you are holy because He is holy. God spoke holiness into you, just as God breathed the breath of life into Adam.
The religious cannot stand this concept, because they want you to earn your holiness, working it out week after week, never attaining, always striving, waiting until you die so you can claim holiness. All that they create is more people who don't trust God, nor believe what God says.
Being holy is for the living, not the dead and holiness starts the moment you are born again, not after you die. I ask you this: Which is better, that you continue to try to attain that which you cannot, or that you receive what God already spoke into you before you were born?