What Is Holiness in the Bible?

Holiness is the defining attribute of God and the central calling of His people. The Hebrew word qadosh and the Greek hagios both carry the idea of separation — being set apart from the common and sinful, and set apart for God's exclusive use. When the angels cry 'Holy, holy, holy, is the LORD of hosts,' they declare that God's very essence is otherness, purity, and moral perfection unlike anything in creation. Believers are called to share this holiness. The New Testament declares that God 'hath chosen us in him before the foundation of the world, that we should be holy and without blame before him in love.' This holiness has two dimensions. Positional holiness is the believer's standing before God at conversion — 'sanctified in Christ Jesus, called to be saints.' Every Christian is a 'saint' (hagios) by virtue of union with Christ. Progressive holiness is the ongoing work of the Spirit conforming the believer to Christ's image. Hebrews commands, 'Follow peace with all men, and holiness, without which no man shall see the Lord.' Peter quotes Leviticus: 'Be ye holy; for I am holy.' Practical holiness involves separation from sin, worldly values, and ungodly associations, as well as positive conformity to God's will. It is not perfectionism — believers will not be sinless in this life — but it is genuine, observable transformation. The means of holiness include the Word of God ('Sanctify them through thy truth: thy word is truth'), the indwelling Holy Spirit, the discipline of suffering, fellowship with other believers, and the mortification of sinful desires. The goal is not merely moral improvement but Christlikeness — reflecting God's character in a fallen world. Holiness is not optional for the Christian; it is the evidence of genuine conversion and the preparation for heaven, where nothing impure can enter.