Jeff Pollard explains in this video that holiness means being set apart for God's use. Far too often, we think of holiness as being related to not doing something. But, when we get too narrow of a focus, we lose the beauty of the biblical picture. Holiness is a life informed by God's Word and it is empowered by God's spirit to mortify sin and to also pursue righteousness and good works as they are defined by Scripture.
1 Peter 1:13-16 (NKJV) - "Therefore gird up the loins of your mind, be sober, and rest your hope fully upon the grace that is to be brought to you at the revelation of Jesus Christ; as obedient children, not conforming yourselves to the former lusts, as in your ignorance; but as He who called you is holy, you also be holy in all your conduct, because it is written, “Be holy, for I am holy.”