A widely used human strategy when someone has to deal with difficulty is autosuggestion. Whenever anything unpleasant comes up, we convince ourselves that it is pleasant rather than unpleasant. This is auto-suggestion. But what the Buddha pointed out is quite the opposite. He never wanted us to hide or disguise an unpleasant matter, the Buddha's teaching encourages us to examine it to the fullest. It is important that we confront the less pleasant aspects of existence, and, to see ourselves in an unbiased way, complete with all our sorrows and inadequacies. Confronting unpleasantness when it arises is really being kind to oneself.
Auto-suggestion means implanting feelings that you don't really have or avoid feelings that you do have. The truth of the matter is that if you are miserable, in reality you are miserable. So rather than avoiding this reality, we have to learn to confront it, to observe it mindfully. The only way out of such phenomenon is to thoroughly examine it. Do this by taking the phenomenon apart piece by piece. Then you are free from such trappings.
Buddha talked about it in this way not because He is pessimistic but because He is optimistic. He has a solution. Life is suffering and that is the real truth. We have to learn to confront this uncomfortable reality of pain, death and illness. To learn how to deal with it is not pessimism, but a very pragmatic form of optimism. Pain is inevitable, but suffering is not. They are two different things. Life can seem pleasant for most of the time, but there comes a time that we have to face the unpleasant. So it is advisable that we invest some of our time and energy in learning to deal with unpleasantness, because some pain is unavoidable.
There are occasions, as in the case of illness, which weaken the mind, when hetero-suggestion has been found to be more effective if you have not yet learnt to confront the situations by self. Hetero-suggestion is used by one person to influence another at times of great illnesses. Here another will help you to think through the Dhamma. The Buddha has shown that the mind is very closely linked with the body that mental states affect the body's health and wellbeing. There is no such thing as a purely physical disease. It is possible so to change one’s mental state grounded in reality, as to cause mental health and physical well-being to follow thereafter.
A couple of examples of what I mean by "hetero-suggestion" in the context of Dhamma:
Maha Kassapa Thera Bojjhanga Sutta is a chant that Buddha recited when both both Ven. Maha Kassapa and Ven. Maha Moggallana were sick. (http://www.accesstoinsight.org/lib/authors/piyadassi/wheel001.html )
Girimananda Sutta was recited when Bhikku Girimananda was diseased, in pain, severely ill. (http://www.accesstoinsight.org/tipitaka/an/an10/an10.060.than.html)
The Supreme Buddha never rejected any activity, if that was wholesome and profitable to the people. The Buddha said that if through some kind of incantation or a mantram, or through a well-spoken word, or through a traditional Act of Truth, or through some mystical power of the Three Refuges, good could be done to the people, then an attempt should be made to bring about that kind of blessing.
- Mahamevnawa Pali-English Paritta Chanting Book
Bhanava is not quite the same thing as auto-suggestion. At some places in the Suttas, the Supreme Buddha explained: “If one does this, these things will happen”. We come across places where Dhamma is explained directly in this manner. In Asavakkhaya Sutta and the Nibbida Sutta, the Supreme Buddha explains, “Oh Bhikkhus, there are five activities which if practiced, if practiced extensively results in the eradication of defilements”. Buddha adviced a bhikku in his deathbed to do this same five meditations. If one feels that there is no possibility of getting liberated from samsara such a person has the fear for samsara. It exists at times of grave illnesses and one has to live in that fear. If an individual is certain that he has a chance of getting liberated from samsara his fear of samsara starts to desipate. The understanding in such a person will turn out to be a realization.
For that you will have to develop the meditation on repulsiveness (Asubha Saññā’) - perceiving the impurity of the body; ‘Ahare Patikkula Saññā’ -perceiving the impurity of material food; ‘Sabba Loke Anabhirata Saññā’ - not taking delight in worlds; ‘Sabba Sankharesu Anicca Saññā’ -impermanence of all aggregates, and of ‘Marana Sati’ -to be mindful of death. (read Asavakkhaya Sutta where the Supreme Buddha explains these five). I could not find the Access-to-insight link, but you can read it in Bhikku Bodhi’s Book.
If these five meditation activities were to be carried out, dispassionateness will arise in you. When you become dispassionate with understanding, then you will begin to lose the desire and craving for materialistic things and sensual pleasures. Your mind will become calmer and calmer. Only with such a calmed mind will it be possible to develop the special wisdoms. Your Sakkaya Ditthi (the idea of self) will leave you. You will see results in this very life.