Holy is both a characteristic of God as well as a lifestyle for us to emulate.
In reference to God, holy means sacred, worthy of worship, praise, and adoration. In the Hebrew culture, a word was repeated three times to place emphasis on it.
This is used with holy in reference to God: “Holy, holy, holy is the Lord God Almighty, who was, and is, and is to come,”(Revelation 4:8; also see Isaiah 6:3).
In regard to people, holy means living according to a moral code or standard. Throughout the Bible, God commands and implores us to be holy. In Leviticus 11:44, God says, “Be holy, because I am holy,” (which is quoted in 1 Peter 1:16.)
The word holy is also attached to other words to elevate them, such as Holy Spirit (Holy Ghost), Holy Communion, Holy of Holies, Holy Bible, and so forth.
Compare to righteous.
Key verse about Holy Spirit: “I baptize you with water for repentance. But after me comes one who is more powerful than I, whose sandals I am not worthy to carry. He will baptize you with the Holy Spirit and fire. (Matthew 3:11,NIV)
A lifelong student of the Bible, Peter DeHaan, PhD, wrote the 1,000-page website ABibleADay.com to encourage people to explore the Bible. His main blog and many books urge Christians to push past the status quo and reconsider how they practice their faith in every area of their lives.