1. All aspirants commit mistakes now in jumping to Samadhi and Dhyana all at once as soon as they leave their houses without caring a bit for ethical perfection. The mind remains in the same condition although they have practiced meditation for fifteen years. They have the same jealousy, hatred, idea of superiority, pride, egoism, etc. Meditation and Samadhi come by themselves when one has the ethical perfection.
2. Sadachara or right conduct is the foundation of Yoga. Yoga is rooted in virtue. Ethical discipline is very necessary for success in Yoga. Ethical discipline is the practice of right conduct in life. One should be well established in Sadachara to begin with. Sadachara is the practice of Yama-Niyama. Yama and Niyama are the two moral backbones of Yoga, which the aspirant must practice in his daily life. These correspond roughly to the ten commandments of Jesus or to the noble eight fold path of Lord Buddha. Practice of Yama-Niyama will eradicate all impurities of the mind.
3. Yama is the very foundation of Yoga, without which the superstructure of Yoga cannot be built. Yama is the practice of Ahimsa (abstinence from injury and killing), Satyam (truthfulness), Asteya (abstinence from theft or falsehood), Brahmacharya (continence) and Aparigraha (abstinence from avariciousness or greed). Patanjali Maharshi mentions the above five chief items for practice in Yama. In every religion you will find this to be the foremost. Great emphasis is given in every chapter of the Gita on the practice of Yama.
4. Niyama is the observance of the five canons, viz., Saucha, Santosha, Tapas, Svadhyaya and Isvara Pranidhana. According to Sandilya Rishi, the practice of Saucha, Daya, Arjava, Dhriti and Mitahara is included in Yama. Saucha is external and internal purity. Washing the hands, taking baths, etc., are for external purity. Filling the mind with pure divine thoughts is internal purity.
5. “The mind becomes pure by cultivating habits of friendliness, compassion, complacency and indifference towards happiness, misery, virtue and vice.” Whosoever shows friendliness towards all those who are found in the enjoyments of pleasures, the dirt of envy leaves him. When the mind shows compassion towards those who are suffering from pain and the wish to remove the miseries of others as if they were his own, the dirt of the desire to do evil to others is removed. Whoever shows complacency towards those who are virtuously inclined beings, the dirt of envy is removed from his mind. Whoever shows indifference towards the vicious and taking to the middle path and not taking sides, towards the viciously inclined, the dirt of the impatience is removed from his mind.
6. By this removal of the characteristics of the qualities of disturbing energy (Rajas) and inertia (Tamas), the characteristic of essential purity (Sattva) manifests itself. He becomes possessed of a very high manifestation of essential purity. His mind becomes inclined to the side of the restraint of mental modifications, because this enlightenment is natural to that state. When the mind becomes pure it attains the state of steadiness and becomes one-pointed. If these moral qualities are not cultivated, the means cannot lead to steadiness. Therefore, one should be well established in Sadachara if he wants to attain perfection in yoga. When one is established in it perfectly, then Samadhi or Nishtha will come by itself.