In the year that King Uzziah died I saw the Lord sitting upon a throne, high and lifted up; and the train of his robe filled the temple. Above him stood the seraphim. Each had six wings: with two he covered his face, and with two he covered his feet, and with two he flew. And one called to another and said:
“Holy, holy, holy is the Lord of hosts; the whole earth is full of his glory!”
And the foundations of the thresholds shook at the voice of him who called, and the house was filled with smoke. And I said: “Woe is me! For I am lost; for I am a man of unclean lips, and I dwell in the midst of a people of unclean lips; for my eyes have seen the King, the Lord of hosts!”
Then one of the seraphim flew to me, having in his hand a burning coal that he had taken with tongs from the altar. And he touched my mouth and said: “Behold, this has touched your lips; your guilt is taken away, and your sin atoned for.”
And I heard the voice of the Lord saying, “Whom shall I send, and who will go for us?” Then I said, “Here am I! Send me.” And he said, “Go, and say to this people:
“‘Keep on hearing, but do not understand; keep on seeing, but do not perceive.’ Make the heart of this people dull, and their ears heavy, and blind their eyes; lest they see with their eyes, and hear with their ears, and understand with their hearts,and turn and be healed.” Then I said, “How long, O Lord?”And he said: “Until cities lie waste without inhabitant, and houses without people, and the land is a desolate waste, and the Lord removes people far away, and the forsaken places are many in the midst of the land. And though a tenth remain in it, it will be burned again, like a terebinth or an oak, whose stump remains when it is felled.” The holy seed is its stump. (Is. 6)
The topic of holiness is one topic that is tragically absent from the mind and thoughts of Christians today. Not only is it frequently neglected, even the very concept of holiness is severely distorted and twisted, both by the conservative Neo-Evangelicals on the one hand and the Traditionalists on the other. Conservative Neo-Evangelicals tend to treat holiness as merely the function of good works as defined by them, and therefore focus on the growing in formation of good moral character and selected spiritual traits as if that is the same as holiness. Traditionalists on the other hand focus a lot on the practice of traditional expressions of Christian piety (ie not eating out on the Sabbath), making such traditional expressions of piety the defining yardstick of Christian holiness, as if the mere keeping of days defines Christian orthopraxy even (cf Col. 2:16).
In the Bible, holiness is an essential and fundamental attribute of God. God is called the thrice holy God (Holy, Holy, Holy), while none of His other attributes are used in such a fashion. (You never read that God is "Love, Love, Love"; "Sovereign, Soverign, Sovereign" etc. although he is both Love and Sovereign). This shows the fundamental importance of holiness as being most definitive of God. God is totally holy, which is to say that He is utterly separate from His creation ontologically, morally, spiritually. This therefore means that nobody can be said to be holy in and of themselves, apart from God making them holy. The irreverance in the cultures and religions of this world is thus blasphemy towards God, as it can be seen in calling religious people or the top religious leader in any religion (even Christianity) "Your Holiness" or something to that effect. Nobody is holy except God alone. Christians who are called saints, that is holy ones, are not holy because they are by nature holy or that whatever they do is holy. We are holy because Christ has died for us, therefore our sins are imputed to Christ while Christ's righteousness is imputed to us. Our holiness is therefore always positionally, counted righteous and holy but never once are we truly holy this side of existence.
As Christians, we are called to be holy, as God is holy (Lev. 11:45; 1 Peter 1:16), and it is not an option! Although we are holy positionally, God has called us to holiness in reality, although it is impossible this side of heaven. Yet we are commanded to strive towards this goal. Since God alone is holy, and we are called to be holy as God is holy, being holy is therefore to become more and more like God in our Christian life. This must be practiced in various ways.
(1) HOLINESS LEADS TO OBEDIENCE TO THE WHOLE OF SCRIPTURE
Holiness translates to obeying the Scripture and all that it teaches; it is not just limited to 'moral' or select teachings in Scripture. Therefore, anyone who obeys only a part of Scripture (ie evangelism) while downplaying or even denigrating others (ie contending for the faith) is most definitely not growing in holines in this aspect. Holiness implies obedience to the entirety of Scripture, Tota Scriptura, not just certain sections or pet topics we like to focus on, as the conservative Neo-Evangelicals tend to be. Not surprising, I for one am wary of one-issue Christians, and all true Christians should be too.
 HOLINESS LEADS TO A BALANCED VIEW OF THE DOCTRINES OF SCRIPTURE
Closely related to the above, holiness calls us to have a balanced view of the various doctrines and teachings of Scripture. Therefore, those who emphasize one doctrine way above its biblical mandate is not growing in holiness in this respect. The error of hyper-Calvinism for example is such a failure both to listen to the whole of Scripture and to submit all theological understanding to the final test of Scripture. More subtle than that of course is the Neo-Evangelicals who call for unity among professing Christians at the expense of Truth, and think somehow that God is pleased when His children are unequally yoked with heretics and false prophets.
(3) HOLINESS LEADS TO AN ELEVATED VIEW OF GOD AND A LOW VIEW OF MAN
One reason why I am unashamedly a Calvinist is because of Calvinism's elevation of God and its denigration of Man. The doctrine of Total Depravity reduces Man to next to nothing. In Is. 6, Isaiah, though a righteous prophet of God, nevertheless see his sin and depravity against the backdrop of the holinessof God and pronounces woe on himself. And all Christians should do likewise. As it is written, 'there is none righteous, no, not one' (Rom. 3:10), and 'the heart is deceitful above all things and desperately sick, who can understand it?' (Jer. 17:9), and 'all our righteous deeds are like a polluted garment' (Is. 64:6). The realization of the holiness of God exposed our depravity and compels us to the Cross of Jesus Christ to beg Him for mercy. Those who think well of themselves in any manner however slight have no true realization of the utter holiness of God. Indeed, those who think that God is under any obligation whatsoever to save anyone on this planet otherwise he is 'not loving' do not truly know God and the depravity of Mankind. When any person truly encounters God like how Isaiah did, their response is to know how wicked and sinful they are and fall on their knees in repentance of their sins. The flippant manner in which many Charismatics talk about their visions of Jesus and God certainly casts significant doubt on whether they have truly talked with God at all in the first place!
(4) HOLINESS LEADS ONE TO LIVE BY GRACE, NOT WORKS
Those who have humbled themselves under God and know Him will live the Christian life by grace, because they know that there is no other way to live it. Since all their righteousness is like filthy rags (NIV; ESV polluted garment cf Is. 64:6), there is simply no point at all to try to live the Christian life by good works, since we cannot merit salvation by it. Furthermore, such working spits on God's free offer of salvation which is to be appropriated only by faith alone in God's grace (Rom. 4:4-5). That said, this is not to say that Christians can sin so that grace may increase (Rom. 6:1). For the believer striving for holiness, he lives for Christ and not for sin, and therefore he strives to do good works, not for salvation but because such pleases God.
(5) HOLINESS LEADS TO SURRENDER TO CHRIST AND HIS LORDSHIP OVER OUR LIVES
Following on the following point, true believers love God and strive to please Him. They would gladly submit to His Lordship as a living sacrifice unto God which is pleasing in His sight (Rom. 12:1). Their lives are therefore no more their own. In the words of the Apostle Paul, they have been crucified with Christ and no longer live, but Christ lives in them (Gal. 2:20a). Like Jesus, they desire to do the Father's will (Jn. 8:29) not their own will, although they may materially struggle with such. And because of that, they will follow Christ whatever the cost, even though they are the only ones left standing after persecution even by nominal 'Christians'. Those who will not submit themselves to the Lordship of Christ or deny it as a 'work' therefore are not growing towards holiness in this aspect.
(6) HOLINESS DOES NOT ALLOW FOR HYPOCRISY AND JUDGMENTALISM
These two points must be said, since it seems that these two sins are the ones most believers are prone to. Yet at the same time, we must be informed by the Scriptures what these two offences means, and not to impose our cultural ideas on the Scriptures. Hypocrisy is antithecal to Holiness on many levels, of which the most important is that it violates the clear command of Scripture. It sometimes comes with its twin Jugmentalism also, which is to say judging people either based on hearsay and error, or with a critical spirit (which must be defined biblically also as a love for putting people down, which no human can judge either). Such Judgmentalism can be seen in a person in the UK whom I've known who maligns me without cause, even though he knows very little about me and most definitely my heart.
This of course is not to denigrate biblical judging (Jn. 7:24), which is commanded by Scripture. What is does condemn is therefore not those who name false teachers and label them as heretics/apostates etc, but those who are selective in their standards of judging others. As it is written, 'For with the judgment you pronounce you will be judged, and with the measure you use it will be measured to you.' (Mt. 7:2) We are to hold ourselves to the same standard we judge others, and ultimately the Scriptures are the standard for so doing.
(7) HOLINESS TRANSFORMS US TO FREED MEN NOT PRINCIPALLY SUBJECT TO ANY AUTHORITY BUT CHRIST, BUT WILLING TO SUBMIT TO ALL GOD-GIVEN AUTHORITY
The two parts must be held in tension here. Christ has freed us from slavery to sin and all things. As it is written, 'So if the Son has set you free, you will be free indeed' (Jn. 8:36). Those who are truly Christians are totally free from all things, and therefore not subject to anyone as a matter of principle. Therefore, as sons of the most high God, we are not bound principally to obey any leaders, tradition etc per se, but to obey God and Him only. However, that said, God has ordained various institutions like the Church , Government and Family to institute His rule over the various aspects of life, and therefore we are to obey them as we obey Christ. Such obedience is therefore primarily towards Christ, not to them as if they deserve such obedience (sometimes they do, oftentimes probably not). Therefore, our allegiance towards Christ here is total and absolute, to others relative to the absolute claims of the commands of our Lord Jesus Christ. (For example, we are NOT to obey any government law which prohibits evangelism)
As we can see, holiness involves total surrender to Christ in every aspect of our lives. And God commands us to be holy. Let us therefore heed God's command and do so as an expression of our love towards Him, for if we truly love Christ, we would obey Him and keep His commandments (Jn. 14:15).