"Be excellent to one another!"

[sophiaserpentia]

If you think that compassion implies softness, there's no way I can describe compassion to you, absolutely no way, because compassion can be very hard. Compassion can be very rude, compassion can jolt you, compassion can roll up its sleeves and operate on you. Compassion is all kinds of things. Compassion can be very soft, but there's no way of knowing that. It's only when you become love -- in other words, when you have dropped your illusions and attachments -- that you will "know." from Anthony De Mello, Awareness.

I define compassion as the sense of being fully aware of the inherent dignity and value of every human being. It's not always an easy thing. But it doesn't always necessarily mean wanting to hug every person you meet, too; there are times when the best course of action involves confrontation, resistance, or even violence.

Compassion is the key to the best course of action in every case. Therefore it is essential in ethical education.

Unconditional compassion is the key that unlocks much of the perennial truth within the world's religions. Unconditional compassion removes the conceptual blockages we may have in contemplating or perceiving the interconnectness of life and spirit.

Unconditional compassion is a much harder road than compassion; think of it as the "high road." 'Compassion' merely asks us to be human to one another; unconditional compassion demands love in all circumstances. Krishna taught Arjuna about compassion while standing in a chariot on a battlefield, even while explaining why the battle had to proceed. Paul and Socrates, like Krishna, taught primarily from the standpoint of compassion. But Lao Tzu, Buddha, and Jesus, among others, taught unconditional compassion.

Those who wish to embody the Tao should embrace all things. To embrace all things means first that one holds no anger or resistance toward any idea or thing, living or dead, formed or formless. Acceptance is the very essence of the Tao. To embrace all things means also that one rids oneself of any concept of separation; male and female, self and other, life and death. Division is contrary to the nature of the Tao. Foregoing antagonism and separation, one enters in the harmonious oneness of all things. -- Lao Tzu, Hua Hu Ching 2

You have heard that it was said, 'Love your neighbor and hate your enemy.' But I tell you: Love your enemies and pray for those who persecute you, that you may be sons of your Father in heaven. He causes his sun to rise on the evil and the good, and sends rain on the righteous and the unrighteous. If you love those who love you, what reward will you get? Are not even the tax collectors doing that? And if you greet only your brothers, what are you doing more than others? Do not even gentiles do that? Be perfect, therefore, as your heavenly Father is perfect. -- Jesus, Matthew 5:43-48

Edit: There is some tension here. What makes this tricky is that while unconditional compassion may be the centerpiece of religious perception, it does not necessarily give the best ethical guidance. It may offer the most spiritual way to perceive the world, but it is not always the best guide to action. Injustice, for example, should not be accepted, it should be opposed. Therefore I take "unconditional compassion" to be a guide to one's inner life; it allows one to cultivate inner stillness; but it is not a guide for living, for interacting with the cosmos.