Lama Zopa Rinpoche

The benefits of reciting OM MANI PADME HUM are like the infinite sky. Depending on how perfectly qualified one’s mind is and on one’s motivation, even reciting OM MANI PADME HUM one time can purify negative karma. For example, a fully ordained monk who has received all four defeats can completely purify that very heavy negative karma by reciting OM MANI PADME HUM one time. So it is very powerful.
Reciting One Thousand Mantras Each Day
In the teachings it is said the benefits of reciting OM MANI PADME HUM are so many that the explanation will never finish. It is explained that if one recites OM MANI PADME HUM one thousand times every day, then one’s children up to seven generations will not be reborn in the lower realms. So if, for example, parents recite one thousand mantras every day then their children, their children’s children and so forth up to seven generations will never be reborn in the lower realms. So parents have quite a responsibility! This is one way that parents can benefit their children and grandchildren.
If one recites the OM MANI PADME HUM mantra one thousand times every day, then one’s body becomes blessed. So when a person who recites one thousand OM MANI PADME HUM every day goes into water, into a river or ocean for example, that water becomes blessed. Whoever that water touches fish, tiny or big animals, or tiny insects, the negative karma of all those sentient beings is purified and they do not get reborn in the lower realms.
If one recites one thousand OM MANI PADME HUM every day, then at the time of death, when the body is burnt, even the smoke that comes from it purifies the negative karma of whoever it touches or whoever smells it. The negative karma of those sentient beings to be reborn in the lower realms is purified.
Fifteen Major Benefits
There are fifteen major benefits, which are the same for both the long and the short mantra. Actually, there are so many benefits but if one can remember these fifteen, these are the most important, the integrated outlines.
1. In all lifetimes, one will meet with virtuous kings - religious kings like His Holiness the Dalai Lama and other virtuous leaders - and by being in such a place where there is a virtuous king one will have much opportunity to practise Dharma.
2. One will always be reborn in virtuous places where there is a lot of Dharma practice, where there are lots of temples, where one can make lots of offerings, where there a lot of holy objects, statues, stupas and so forth. Being in a place where there are all these holy objects gives one the opportunity to practise Dharma, to create the cause of happiness, to accumulate merit. And being in a place where there are many in the city doing practice inspires oneself to practise Dharma, the cause of happiness.
3. One will always meet with fortunate times and good conditions, which will help your Dharma practice. Having many good things happen it inspires you to practise Dharma, to receive teachings and to meditate.
4. One will always be able to meet with virtuous friends.
5. One will always receive a perfect human body.
6. One’s mind will become familiar with the path, with virtue.
7. One will not allow one’s vows, one’s morality to degenerate.
8. People around you - family, Dharma students, people in the office, and so one - will be kind and harmonious with you.
9. You will always have wealth, the means of living.
10. You will always be protected and served by others.
11. Your wealth will not be stolen or taken away by others.
12. Whatever you wish will succeed.
13. You will always be protected by virtuous nagas and devas.
14. In all lifetimes, you will see Buddha and be able to hear the Dharma.
15. By listening to the pure Dharma, you will be able to actualise the profound meaning, emptiness.
It is said in the teachings that anybody who recites this mantra with compassion - devas or humans - will receive these virtues. In addition, the mantra has the power to heal many diseases and to protect from any harms.
The Compassionate Buddha manifesting in the form of the mantra leads us to enlightenment. In relation to the Holy Body of the Compassionate Buddha we make offerings, accumulate merit, purify and meditate. Then the Compassionate Buddha manifests in the form of the mantra OM MANI PADME HUM. Reciting this mantra unifies our negative karma and causes us to actualise the whole path from guru devotion through renunciation, bodhicitta, and emptiness up to the two stages of tantra. Then we are able to bring all sentient beings to enlightenment. That is how the mantra benefits us. It is the Compassionate Buddha’s holy speech manifesting in an external way in order to benefit us.