Dr Sharib says "Al Quddus is the One Who is free from limitations of all sorts.
The human understanding cannot determine Him.'

To emulate the Name you should free yourselves from all except God and you
should try to abstain from committing sins."

Appropriate recitation can save one from spiritual ailments such as greed and
lust, and protect one from one's enemies or free one from the discomforts and
monotony when journeying.

see 'The 99 Most Beautiful Names of Allah' by Dr Zahurul Hassan Sharib

Some other references:

Al-Ghazali says: "In sum sensory and imaginary perceptions are shared with
animals, and one should rise above them in favour of what is properly human
.......The aspirant is as exalted as the object to which he aspires, as one who is
intent on what enters his stomach is as valuable as what comes out of it, but
whoever is intent on nothing except God - Great and Glorious - finds the level
commensurate with his intent. And whoever elevates his mind.......and frees his
will from the dictates of passion will lodge in the abundance of the garden of

(Al-Ghazali - The Ninety-nine Beautiful Names of God. Trans. Burrel/Daher: ITS: 1992.)

Sheykh Tosun Bayrak says :"This is one of the five qualities that indicate the
non-resemblance of Allah to anything."

"To find the feeling of Al-Quddus in oneself one should work on ........eliminating
doubts in oneself."

The Most Beautiful Names: Sheikh Tosun Bayrak al-Jerahi al-Halveti:Threshold Books 1985

"Make clean your hearts within;
Cast forth each inmost sin,
Then with bowed brows say this name and adore.
Forgive, Thou Pure One! -Whom we bless -
Of our good deeds the sinfulness."

Sir Edwin Arnold: Pearls of Faith: Ashraf: 1961
Bismillah ir Rehman ir Rahim
Qur'an 62:1
The Holy
The Most Holy
"Whatever is
In the heavens and
On earth, doth declare The praises
and Glory
Of Allah, - the Sovereign, The Holy
One, the Exalted in Might, the Wise."  
"Yusabbihu lillaahi maa fissamaawaati
wa maa fil-'arzil-Malikil-Qudduusil

(Qur'an 62:1 trans:Y.Ali)