A. C. Bhaktivedanta Swami Prabhupada

...God is there. Otherwise Chaitanya Mahāprabhu, as soon as He entered the Jagannātha’s temple, immediately He fainted. Does it mean He made a fun? No. He saw the Supreme Personality of Godhead present there.

So it requires eyes to see God. That eyes you have to prepare. What is that eyes? Premāñjana-cchurita-bhakti-vilocanena [Bs. 5.38]. You have to apply eyes’ ointment. Just like there is some medicine, eye ointment, which you apply — you can see very distinctly — similarly, that ointment is premāñjana. If you develop love for God Just like Chaitanya Mahāprabhu. He is in ecstasy, always in love. He can see. Similarly, if you develop your love for God, then you can see. Premāñjana-cchurita-bhakti-vilocanena [Bs. 5.38]. This premāñjana, this ointment of love is bhakti. 

- A. C. Bhaktivedanta Swami Prabhupada

Swami Rama

The aim of life is Self-realization. The saying, “Know thyself,” was written on the temple of the oracle at Delphi in ancient Greece. This is where East and West meet. Both East and West agree on this goal, though they might hold different ways of attaining it.

The one important part of life is ignored by the educational systems at home, in society, and in the colleges and universities: “Know thyself.” You need to understand yourself on all levels.  You don’t need much external information; you already have true knowledge within. You need to learn how to apply the knowledge that you have.

All the practices, therapies, remedies, and all the exercises whatsoever, are not really meant for the body or the soul. The soul is perfect; it doesn’t need any exercise or meditation. The soul needs no improvement. If you meditate, there will be no change in the Spirit. You need to meditate and you need help, not for the soul, but for your mind. As the great Upanishads say, “The mind is the instrument that can become either a means of liberation or a means of bondage.” Thus, you should understand the nature of your mind. It’s easy to say that, but it’s not so easy to actually know it. When you want to study the mind, how do you actually do it? You don’t have any external device or instrument to use to study the mind, so you have to train one of the aspects of your mind to study the totality of the mind. You have to train a part of the mind, so that all the functions of the mind can be studied through the use of that one part.

The first real step of development in life is to know yourself, not to talk about knowing God. This is a journey within; you are trying to explore who you are, so that you can function well in your life, understand your habit patterns, and learn to live happily in the world. 

Sri Nisargadatta Maharaj

Nisargadatta himself tells of his time with his Guru, and what transpired in the more mature phase of his spiritual practice (sadhana):

My Guru told me: “...Go back to that state of pure being, where the ‘I am’ is still in its purity before it got contaminated with ‘I am this’ or ‘I am that.’ Your burden is of false self-identifications—abandon them all.” My guru told me, “Trust me, I tell you: you are Divine. Take it as the absolute truth. Your joy is divine, your suffering is divine too. All comes from God. Remember it always. You are God, your will alone is done.” I did believe him and soon realized how wonderfully true and accurate were his words. I did not condition my mind by thinking, “I am God, I am wonderful, I am beyond.” I simply followed his instruction, which was to focus the mind on pure being, “I am,” and stay in it. I used to sit for hours together, with nothing but the “I am” in my mind and soon the peace and joy and deep all-embracing love became my normal state. In it all disappeared—myself, my guru, the life I lived, the world around me. Only peace remained, and unfathomable silence. 

(I Am That, Dialogue 51, April 16, 1971)