Excerpts from Buddhist text and publications.
On one occasion, while The Buddha was passing through a forest. He took a handful of leaves and said: "O Bhikkhus, what I have taught is comparable to the leaves in my hand. What I have not taught is comparable to the amount of leaves in the forest.
Monks, even if a monk should take hold of the edge of my outer garment and should walk close behind me, step by step, yet if he should be covetous, strongly attracted by pleasures of the senses, malevolent in thought, of corrupt mind, an purposed, templative, scatter-brained, his sense-faculties uncontrolled, then he is far from me and I am far from him.
  Monks, if a monk should be staying even a hundred miles away, yet if he is not covetous, not strongly attracted by the pleasures of the sense, not malevolent in thought, not of corrupt mind and purpose, his recollection firmly set, attentive, contemplative, his thought be one-pointed, restrained in his sense-faculties, then he is near me and I am near him.
Buddha to Ananda: It may be Ananda, that ye shall say: 'The world had lost its master, we have no master more.' Ye must not think thus, Ananda. The Dhamma, which I have taught unto ye, this is your master when I am gone hence. Be mindful, be righteous and be vigilant. Be lamps unto yourselves. Transient are all component things. Strive on with needfulness.
If anyone were to speak ill of me, my doctrine or my disciples, do not bear any ill-will towards him, do not be upset or be perturbed at heart, for if you were to be so it will only cause you harm. On the other hand if anyone were to speak well of me, my doctrine and my disciples, do not be overjoyed, thrilled or be elated at heart, for if you should be so it will only be an obstacle in your way of forming a correct judgment as to whether the qualities of praised are indeed real and actually found in us.
If you judge by yourselves - these actions are demeritorious, these are wrong, these are despised by the wise and these are conducive to the prejudice and grief of him who commits them - then do shun them.
  If you judge by yourselves - these actions are meritorious, these are right, these are praised by the wise, these are conducive to well-being for the happiness of him who performs them - then act accordingly.
As a wise man tests gold on a touch-stone, heating and cutting, so you, monks should test my words by practice, and not accept them simply due to the reverence to me.
When a simpleton abused him, Buddha listened in silence; but when the man finished, Buddha asked, "Son, if a man declined to accept a present made to him, to whom would it belong?" The man answered, "To who offered it."
  "My son." Said Buddha, "I decline to accept your abuse, and request that you keep it for yourself."
In the self same way, disciple, a certain monk may be very kind, very gentle, very quiet, so long as no unpleasant words are uttered. When, however, people begin to say unpleasant things of the monk - then is the time to see if the monk is kind, or if he is gentle or if he is quiet.
Rituals have no efficacy; prayers are vain repetitions; and incantations have no saving power. But to abandon covetousness and hurt, to become free from evil passions and to give up hatred and ill-will, that is the right sacrifice and the true worship.
Therefore, be ye lamps unto yourselves, be a refuge to yourselves. Hold fast to Truth as a lamp; hold fast to the truth as a refuge. Look not for a refuge in anyone beside yourselves. And those, who shall be a lamp unto themselves, shall betake themselves to no external refuge, but holding fast to the Truth as their lamp, and holding fast to the Truth as their refuge, they shall reach the topmost height.
Do not believe in anything simply because you have heard it. Do not believe in anything simply because it is spoken and rumored by many.? Do not believe in anything simply because it is found written in your religious books. Do not believe in anything merely on the authority of your teachers and elders. Do not believe in traditions because they have been handed down for many generations. But after observation and analysis, when you find that anything agrees with reason and is conducive to the good and benefit of one and all, then accept it and live up to it.
When you listen to the Dharma you must open up your heart and compose yourself in the centre. Don't try to accumulate what you hear or make a painstaking effort to retain what you hear through memory. Just let the Dharma flow into your heart as it reveals itself, and keep yourself continuously open to its flow in the present moment. What is ready to be retained will be so, and it will happen of its own accord, not through any determined effort on your part.
  Similarly, when you expound the Dharma, you must not force yourself. It should happen on its own and should flow spontaneously from the present moment and circumstances. People have different levels of receptive ability, and when you're there at that same level it just happens, the Dharma flows.