Holiness is a facet of God/Source. We are a facet, a part of that great "oneness" the bible speaks of.

There are many 3 dimensional concepts of holiness which I will leave to the theologians and evangelical Christians amongst us.

I will leave you with this thought, you are entirely Holy independent of how you feel or what you do. You may "feel" it and this is great. But when you don't feel it you still are it.....Why ? because you are the Christ spoken of in scripture. Your not a follower of Christ or a believer in Christ ....you are that Christ. So your Holy by default Jai :) Good news eh !

What makes a person Holy is letting God live within us. It is not only letting God live within us but as well be in control over us. It is confessing our sins to Christ and accepting his forgiveness so we can live in him and he in us. When you live for God and be and act as God would in all situations. You treat all people as God would treat them, and as if they were God. You would not want to hurt God, neither would you want to hurt others. You would not want to offend God, neither would you want to offend others. You let God come through to bring peace and healing to all you meet. You keep God's statutes always and devote your life and self to the service of God and others.

I think holy hasn't to do with religion. It is interspersed in relationship with God.

I think of the movie Another Perfect Stranger where Jefferson Moore as Jesus is talking with the girl on the plane. She says she hates religion, he agrees with her. But then shows her about relationship with God.

Religion is more the set rules, regulations, and rituals. But relationship with God is knowing God personally. In Isaiah there is a verse that says Abraham was known as a friend to God. This is something far more that I would consider holy than someone that performs rituals and kneels down bowing to the floor saying a thousand times a day God is great, the all mighty, all knowing, I praise you to the highest, you are the best.

All of that plus burning candles, ringing bells, singing praises. All of that is nothing compared to talking with God, seeing God is everywhere in everyone and everything including yourself.

That to me is holy. Would a father rather be hugged and loved or respected from a distance? Those are two very different responses and both bring very different results.

The first results in a closeness and that you can even grow to become like. The second seems to keep a mystery like you are awed by him and can never measure up to him. The first you feel that your relationship is strong and anything you need or want just ask and it will be done. The second one you know God is powerful and can do anything you need or want but wonder if you are worthy, have I praised God enough, have I bowed to him enough, have I prayed enough, was I good enough for him? He'll grant my prayers if I am worthy and if he wants to.

Religion places you aloof from God if you let it be so. It is there to show you a path but don't get caught up on the path that you never find the destiny. It is similar to the labyrinth, you can find the center and the great treasure there is, or you can get trapped and lost in the labyrinth forever.

Relationship is the key, Jesus came so that we can have direct relationship with God. We can know God personally right now right here, we need no intercessor, we need not do anything to be worthy but accept him.

I feel we all are holy including you too. All is God, because all is God then all have that same holiness but do not know. It is like all have amnesia and do not realize how beautiful and wonderful they really are.

Here is a great work on the subject, from a medieval Christian perspective, which might be in the sort of vein you are looking for:

http://www.rgle.org.uk/Llull_B_C.htm

http://www.wwnorton.com/college/english/nael/middleages/topic_1/lull.htm

There is also this one, which I couldn't find online: "L'Ordene de chevalerie"

one is holy when he is born of water and spirit, in truth with out division when is mind and heart work in perfect balance in truth(born of water) when the water(soul) and spirit solve their division and become one again(born of spirit) with out fear he can enter the last narrow door and lift up the little child(son or daughter of man)above to the kingdom of the peacemakers and the pure of hearts. I testify that it is the truth. I am the way the truth and the life. I know where I come from and where I am going. and also will you when you have went back above. I am not a divider am I?

Let there be light, be the light that you can be, experience and enjoy.

and to answer your question:

Is a man who lives alone in a cave and seeks God Holy? yes he is if he is the light that he can be.

Or does Holiness require interaction with people? the work needs to be done inside if one is not divided inside he is not divided out side so even if he does not interact with people outside often you will see that people divide them self from the truth and cannot receive it. yes he is holy.

Can an ordinary person be Holy? what is your definition of ordinary? is it on what you judge on the outside? are all person made the same way that you are made in the image of god and born to this world so who is not in the flesh ordinary? why seek that division?

Will also say that if people would truly believe in Jesus they would be able to understand what he said and know is teaching, they would seek and find. since that when you believe in something it as to have some truth and you follow those truth. maybe they missed the seek you first the kingdom of God or follow the word, the word is truth. they honor me with their lips but their heart is far from me. some are very far they create division about race or believe only on the flesh and the blood, did not Jesus said you judge after the flesh, I judge no men but if I judge my judgment is true. did not Jesus said clean the inside of the cup. what about the greatest commandment and the second greatest commandment what about the beatitude and what he said to Nicodemus. I could say many other things but I will do what please him. many have heard but did not understand.

Let there be light, be the light that you can be, experience and enjoy.