In his superb book, The Tibetan Book of Living and Dying, Sogyal Rinpoche describes bodhicitta, the thought of awakening, like this:
To awaken and develop the heart of the enlightened mind is to ripen steadily the seed of our buddha nature, that seed that in the end, when our practice of compassion has become perfect and all-embracing, will flower majestically into buddhahood. Bodhicitta, then, is the spring and source and root of the entire spiritual path.”
I’m not sure any other spiritual tradition than Buddhism has a concept such as bodhicitta, the aspirational wish to realize awakened mind for the benefit of all living beings. And for our path, as Sogyal Rinpoche says, it is the spring, source and root of the all spiritual development.
Shantideva, the eighth century Indian Buddhist poet and philosopher, understood the importance of bodhicitta well, and that is why in Chapter One of A Guide to the Bodhisattva Way of Life, he wrote,
A person who wants to overcome the sorrows of life, who wants to still the sufferings of sentient beings, who wants to experience happiness of the spirit, must never abandon the thought of awakening.
And in Chapter Three,
Once a person of wisdom has given rise to the the thought of awakening, that person shall exalt the same thought repeatedly in the following manner, in order to secure its subsequent growth:
“Today my life bears fruit, and this human state is well assumed; today I have been born in the family of Buddhas, now I become a child of the awakened.”
From today on, I must act according to the customs of my family, so that the legacy of this noble lineage may be fulfilled.
It as if a blind man found a gem in a pile of dung. In the same manner, I know not how, this thought of awakening has arisen in me.
This elixir has arisen to vanquish death from the world. It is the inexhaustible treasure that will alleviate thirst in the world, the unsurpassed medicine that will allay the sufferings of the world . . .
The caravans of men, which travels through the roads of existence, hungering for pleasure and happiness, finds here the banquet of bliss, in which all those who come to it become satiated.
Today in the presence of all the Noble Ones, I invite the whole world to be guests at the festival of awakening, and at the same time, to happiness. May all living beings rejoice.”