4. Al-Quddus, The Holy One, The Pure One

According toTafsir Ibn Kabir, "(Al-Quddus,) meaning "The Pure,'' according to Wahb bin Munabbih, while Mujahid and Qatadah said that Al-Quddus means "The Blessed.'' Ibn Jurayj said that Al-Quddus means "He Whom the honorable angels glorify.'' "

What does it mean to be holy or pure?   If we think about purity in natural things, it is very short-lived, and one might almost say fragile.  We are clean until we get dirty.  A piece of white paper is clean only as long as it is not used.  A cup of water becomes impure as soon as anything is added.   That which is holy is set apart for God, with a certain amount of fear lest it become unclean before the offering is accepted.

It is God alone whose purity is such that God not only remains eternally pure, but has the power  to transfer that purity to others, to make them clean. When the prophet Isaiah saw a vision of the Lord, he saw him

seated on a throne, high and exalted, and the train of his robe filled the temple. Above him were seraphs, each with six wings: With two wings they covered their faces, with two they covered their feet, and with two they were flying. And they were calling to one another:
“Holy, holy, holy is the LORD Almighty;
the whole earth is full of his glory.”  Isaiah 6:1-3

(Notice that here we do see the angels glorifying God in conjunction with his holiness, as Ibn Jurayj mentioned.)

In the Hebrew, the word is Kadosh, and it is related to the Arabic Quddus.  Isaiah's response was immediately to be aware of his own impurity in contrast to the holiness of God.  He cried out, "Woe to me, I am ruined! For I am a man of unclean lips, and I live among a people of unclean lips, and my eyes have seen the King, the LORD Almighty” (Isaiah 6:5).  God sent a seraph to touch his lips with a burning coal to take away his sin.

In the New Testament, it is Jesus who is portrayed as having this kind of contagious purity.

More really Christian stuff:

An unclean woman touches his clothes. Instead of making him impure, she gets healed.  He touches lepers. Instead of getting leprosy himself, their leprosy is healed. And perhaps most startling of all, he claimed the ability to forgive sin.  The people around were offended, and thought this was blasphemy. If Jesus had not been God, it would have been blasphemy. (Anyone can forgive sin against themselves. But Jesus was talking to a stranger with no sense in the story that the man had done something to Jesus as a man.)

Oh God, I want to have your kind of purity in my life, to be completely and totally given over to your love and your ways.