Believe nothing, O monks, merely because you have been told it ... or because it is traditional, or because you yourselves have imagined it.  Do not believe what your teacher tells you merely out of respect for the teacher.  But whatsoever, after due examination and analysis, you find to be conducive to the good, the benefit, the welfare of all beings - that doctrine believe and cling to, and take it as your guide. - Gautama Buddha
As rain penetrates an improperly shingled roof, so passion overwhelms a confused mind. - Buddha
Having slain anger, one sleeps soundly;
Having slain anger, one does not sorrow;
The killing of anger,
With its poisoned root and honeyed tip:
This is the killing the noble ones praise,
For having slain that, one does not sorrow.

-        Buddha, "The Connected Discourses of the Buddha"
Even as a great rock is not shaken by the wind, the wise man is not shaken by praise or blame.

A questioner asked the Buddha: "I would like to know about the state of peace, the state of solitude and of quiet detachment. How does a person become calm, independent, and not wanting to grasp at anything?"

"A person does this," replied the Buddha, "by eradicating the delusion of 'I am.' By being alert and attentive, he begins to let go of cravings as they arise. But whatever he begins to accomplish, he should beware of inner pride. He must avoid thinking of himself as better than another, or worse or equal, for that is all comparison and emphasizes the self.

"The person should look for peace within and not depend on it in any other place. For when a person is quiet within, the self cannot be found. There are no waves in the depths of the ocean, it is still and unbroken. It is the same with the peaceful person. He is still, without any longing to grasp. He has let go the foundations of self and no longer builds up pride and desire."
- Sutta Nipata
We are not compelled to meditate by some outside agent, by other people, or by God. Rather, just as we are responsible for our own suffering, so are we solely responsible for our own cure. We have created the situation in which we find ourselves, and it is up to us to create the circumstances for our release.
- Lama Thubten Yeshe, "Wisdom Energy"
By charity, goodness, restraint, and self-control men and women alike can store up a well-hidden treasure -- a treasure which cannot be given to others and which robbers cannot steal. A wise person should do good -- that is the treasure which will not leave one. - "Khuddhaka Patha"
The realm of reality is as vast as cosmic space; it is the knowing mind of sentient beings that is small. Just as long as you do not become egotistic and selfish, you will be ever sated with the spiritual food of nirvana. - Pao-chih
A head of gray hairs
Doesn't mean one's an elder.
Advanced in years,
One's called an old fool.

But one in whom there is
Truth, restraint,
Rectitude, gentleness,
He's called an elder,
His impurities disgorged,

- Dhammpada, 19, translated by Thanissaro Bhikkhu

All that we are is the result of our thoughts; it is founded on our thoughts and made up of our thoughts. With our thoughts we make the world. If you speak or act with a harmful thought, trouble will follow you as the wheel follows the ox that draws the cart.

All that we are is the result of our thoughts; it is founded on our thoughts and made up of our thoughts. With our thoughts we make the world. If you speak or act with a harmonious thought, happiness will follow you as your own shadow, never leaving you. 
- Dhammapada
The one who thinks himself equal or inferior or superior to others is, by that very reason, involved in argument. But such thoughts as equal, inferior, and superior are not there in the one who is not moved by such measurements.

Why should a wise person argue with another, saying: "This is a truth" and "This is a lie"? If such a one never entertains a thought about equal, inferior, or superior, with whom is he going to argue?

The sage who has freed himself from dependence on others and from dependence on words and is no longer attached to knowledge does not risk the smothering of truth by engaging in disputes with people.  - Sutta Nipata
If you want to know the past, to know what has caused you, look at yourself in the present, for that is the past’s effect.  If you want to know your future, then look at yourself in the present, for that is the cause of the future. - Majjhima Nikaya
Whatever attitudes we habitually use toward ourselves, we will use on others, and whatever attitudes we habitually use toward others, we will use on ourselves.  The situation is comparable to our serving food to ourselves and to other people from the same bowl.  Everyone ends up eating the same thing--we must examine carefully what we are dishing out. - Bhante Henepola Gunaratana, "Eight Mindful Steps to Happiness"
It is necessary to cultivate some discipline of mind, for an undisciplined mind always finds excuses to act selfishly and thoughtlessly.  When the mind is undisciplined, the body is also undisciplined, and so is speech and action. - From "Buddha Speaks," edited by Anne Bancroft, 2000.
Adopting an attitude of universal responsibility is essentially a personal matter.  The real test of compassion is not what we say in abstract discussions but how we conduct ourselves in daily life. - His Holiness the Dalai Lama, "Imagine All the People”
The mind is often compared to a horseman and the breath to the horse.  A wild and untamed horse is difficult for the rider; a very good and well-trained horse is quite useful.  If both rider and horse are extremely well trained and skilled, an excellent combination has been made. - Chokyi Nyima Rinpoche, “Union of Mahamudra and Dzogchen”
Even as rain breaks through an ill-thatched house,
So lust breaks through an ill-trained mind.

Even as rain breaks not through a well-thatched house,
So lust breaks not through a well-trained mind.

- Dhammapada 13-14
But what makes these 'experts' preach their opinion and call it truth?" asked the inquirer. "  Is it an inheritance of humankind to do this, or is it merely something they gain satisfaction from?"
"Apart from consciousness," answered the Buddha, "no absolute truths exist.  False reasoning declares one view to be true and another view wrong.  It is delight in their dearly held opinions that makes them assert that anyone who disagrees is bound to come to a bad end.

But no true seeker becomes embroiled in all this.  Pass by peacefully and go a stainless way, free from theories, lusts and dogmas.” - Majjhima Nikaya
All beings tremble before violence.
All fear death.
All love life.

See yourself in others.
Then whom can you hurt?
What harm can you do?

- Dhammapada 129-130
Right speech, harmlessness,
Restraint in speaking ill of others,
Moderation in food, at peace in remoteness and solitude,
Devotion to higher meditation.
This is the teaching of the Buddhas.

- Dhammapada 185
Your own self is
your own mainstay,
for who else could your mainstay be?
With you yourself well-trained
you obtain the mainstay
hard to obtain.

- Dhammapada 12, translated by Thanissaro Bhikkhu
Our first priority should be to prepare a long-term strategy for improving the state of the world that focuses on the coming generations.
- His Holiness the Dalai Lama, "Imagine All the People"
To be attached to one's own happiness
is a barrier to the true and perfect path.
To cherish others is the source
of every admirable quality.

- Tsongkhapa, "The Splendor of an Autumn Moon"
Enlightenment is a way of saying that all things are seen in their intrinsic empty nature, their Suchness, their  ungraspable wonder.  Names or words are merely incidental, but that state which sees no division, no duality, is enlightenment. - Prajnaparamita
Everything is as it is. It has no name other than the name we give it. It is we who call it something; we give it a value.  We say this thing is good or it's bad, but in itself, the thing is only as it is.  It's not absolute; it's just as it is.  People are just as they are. - Ajahn Sumedho, "The Mind and the Way"
Walking the spiritual path is a very subtle process; it is not something to jump into naively.  There are numerous sidetracks which lead to a distorted, ego-centered version of spirituality; we can deceive ourselves into thinking we are developing spiritually when instead we are strengthening our egocentricity through spiritual techniques. - Chogyam Trungpa, "Cutting Through Spiritual Materialism"
Sitting peacefully on a cushion day and night seeking to attain Buddhahood, rejecting life and death in hopes of realizing enlightenment, is all like a monkey grasping at the moon reflected in the water. -  Shoitsu From "The Pocket Zen Reader," edited by Thomas Cleary, 1999.
Do not form views in the world through either knowledge, virtuous conduct, or religious observances; likewise, avoid thinking of oneself as being either superior, inferior, or equal to others.

The wise let go of the “self” and being free of attachments they depend not on knowledge. Nor do they dispute opinions or settle into any view.

For those who have no wishes for either extremes of becoming or non-becoming, here or in another existence, there is no settling into the views held by others.

Nor do they form the least notion in regard to views seen, heard, or thought out. How could one influence those wise ones who do not grasp at any views? - from the Sutta-nipata