By Sant Kirpal Singh, from the book "Spirituality – what it is", chapter 11

For the unifying experiment of soul with oversoul, one has to enter into the laboratory of the human body, just as a student of science enters the science room for a scientific experiment and closes all the doors and windows, so that the noise and stir from outside may not disturb him in his work. Again, on the table before him are arranged various articles and instruments, all neat and clean for handling, before he, under the guidance and instructions of the science master, starts making the experiment. He moves with a single-minded purpose, a well-pointed attention and a whole-hearted devotion. He may fail once or twice, but he does not lose heart in his endeavours and repeats the process over and over again until he succeeds. In exactly the same way, the spiritual experiment is to be carried on in the human body, after closing down all the physical senses, so as to keep out the noise and bustle of the world.

This process of going-in, consists in withdrawal of the sensory currents and focusing them at the seat of the soul, or consciousness, at a center behind the two eyebrows. In other words, the spirit, which at present is pervading the entire body from top to toe and is identified with the world, is gathered up and collected at one place, until one loses the very idea of having a body at all. Having closed down all the outlets of attention, the spiritual experiment is now to be started in the presence of the Master-soul and under His guidance and instructions, the whole process to be gone through with scrupulous attention and loving devotion.

Then you are no longer a physical entity but a pure spirit. So also is the luminous form of the Master – sound personified – Naam, Shabd, Sruti, Naad, hidden music, or call it what you will. To link the spirit with it can only be done when the mind is freed from mental oscillations and the intellect is at perfect rest, so that a halcyon calm is established both within and without.

Mere washing of the body can be of little avail. Inner cleanliness must precede outer cleanliness. The mind must first be cleansed and purified of all desires, anger, hankering, attachment and egotism, before you start with the spiritual experiment.

By washing outside, without washing the mind within,
one loses both here and hereafter,
Ever tormented by lust and anger, he is lost and bewildered. – Asa M.5

Prophet Mohammed, too, laid great emphasis on the purity of the mind. He used to say that Namaz (prayer) was the key to Jannat (paradise), and the purity of heart was the key to Namaz; and again, that chastity was more than half-way house on the path Godwards.

St. Matthew tells us: "Blessed are the pure in heart, for they shall see God."
But inner cleanliness cannot come by washing the body alone. The bodily dirt can, of course, be washed off by water, the pollution can be cleansed by means of soap, but the sinful mind is cleansed by communion with the Word.

Guru Nanak therefore tells us:
When the limbs of the body are besmeared, they are washed clean with water;
When the clothes get dirty and polluted, they are cleansed by soap;
When one's mind gets defiled by sins, it can be purified only by communion with the Word. – Jap Ji, St. 20

We can commune with and practice the Word by linking the inner consciousness with the Sound-principle, but for this, one has, in the first instance, to subdue the mind and the senses.

He who can control the ten senses, he may see the light of heaven. – Gauri M.5

The spirit which alone is to make the experiment can do nothing when it is altogether lost in the stormy seas of passions. It is tossed on the billows like a leaky boat with no rudder to guide its course and is driven helplessly by the chance winds and waters around it.

Unless one gets an actual experience of the self and of God, one cannot believe and have unshakable faith in the existence of God. The saints and Master-souls do, in fact, transcend the limitations of the three bodies, physical, astral and causal, and really get the experience of, and a contact with, the reality within. As such, they are competent enough to guide mankind on the highroad to God, for they do speak from actual experience and not from hearsay or secondary knowledge gathered from ancient texts or through learned priests and pandits.

Listen ye to the true testimony of saints;
They give out what they actually witness. – Ramkali M.5

Again, such God-men never ask a person to have just a blind faith in their teachings. On the contrary, their clarion call is, "Believe not the word of a Master-saint, unless thou hast an actual experience of what he saith."

Until I see the truth with my own eyes,
I cannot be fully convinced of what the Master says. – Swamiji

When I saw (the truth) with my own eyes,
Then in truth I put faith in the Master's words. – Tulsi Sahib

The Mastersouls believe in the direct testimony of the experiencing spirit. They, like Rishi Ashta Vakar, are capable of delivering goods right here and now. The Masters do not hold out empty promises, which may or may not come true, nor give false hopes, which may or may not materialize. Their religion is one of pure gold at the counter, and not one of mere credit. Why, then, should one engage in observance of rites and rituals, and performance of meritorious deeds, in the hope of securing some posthumous and uncertain rewards? Human birth is too precious and human life, alas, too brief to be frittered away in useless pursuits that may bear no fruit in the long run.