Buddhism teaches that the source of unwholesome karma comes from our mind, speech and action. Therefore, to realistically change one's life and subsequently the conditions in the external world for the better, we should start from these three areas.
To think good thoughts, we should train ourselves to be free of doubt, jealousy, greed, anger and hatred, and instead develop good intention, compassion, kindness, benevolence, motivation and vows. Bearing good thoughts refers to cultivation of good mental habits and to have positive attitude always even in the midst of adversity. Be still while caught in a chaos, be calm when everything is in a turmoil and sticking to peace when everyone around you is at war are qualities that Buddha has always encouraged his followers to cultivate. Cultivating these qualities is the practice of bearing good thoughts.
To speak good words, to cultivate good speech karma, which means one should not lie, nor engage in duplicitous, harsh or trivial speech. When one speaks, one’s words should be kind, rational, responsible, wise and truthful. Quoting from Buddha himself, "If you propose to speak, always ask yourself, is it true, is it necessary, is it kind?” Words, when use constructively, have the power to bring healing, wisdom, guidance and enlightenment. Words are a gift to mankind, and the usage of words is a privilege that has set us apart from animals. When use correctly and constructively, words have the power to encourage people, and even save lives.
To do good deeds is to practice taking action towards benefiting others with kindness and compassion, and refrain from harming or bringing hurts to the lives of other people. Every kind deed is like a seed, that can grow into a tree, and multiple into a good harvest. Never underestimated the power of any small good deed in our lives.
The three karmas of mind, speech, and action, as explained by Buddhism, can be practiced both positively and negatively. When we use these three karmas to do good, then we can be reborn in heaven; if we use them to commit wrongdoings, we may find ourselves in hell. Note that reborn happens at every moment of existence, and heaven and hell do not exist after death. Every current moment can be heaven or hell, depending on how men make of the present.
Therefore, following the three acts of goodness affects our future immensely. It even affects the whole community, nation and subsequently the world, for the positive and negative morale of a society depends on the three karmas of body, speech, and mind of its citizens.
If we all bear good thoughts, then we will find respect, peace and harmony anywhere we go. If we all say good words, then what we always hear will be music to our ears and medicine to our hearts. If we all do good deeds, then through helping one another valuable human relationships can be established and many lives can be changed for the better. Finally, thinking good thoughts, speaking good words and doing good deeds is the fastest shortcut to create heaven in our world.