There are some conditions which a bhakta cannot afford to overlook. One must cultivate the faculty of discrimination, viveka, and with its help live in the world in such a way that the world may not produce any effect on one’s being. Ramanuja calls it avoidance of annadosha, defects of food. Shankaracharya, however, speaks of the doshas, faults, of all sense contact. The idea is to live without being affected by the world. Live at a higher mental level and never have association with tempting objects of the senses.
Ramanuja also talks of freedom from desires, vimoka. Never
indulge in fulfilment of desires, otherwise life will be destroyed, as if blown
away by a cyclone. Make it a principle; otherwise, bhakti
will not remain. As long as you are a sadhaka, you must eschew all desires.
This must be accepted on
principle. If you give up indulgence in desires on principle then you will be
free from psychological
reactions.
Ramanuja also speaks of abhyasa, kriya, and kalyana. Only
observing ‘don’ts’ or abstentions, without performing sadhana, will be
ineffective. You must change the direction of your life through abhyasa,
repeated practice. If the direction is towards enjoyment, control will be of no
avail. Kriya means doing good to others with feeling. Only kriya done with
feeling can be called sadhana, mere mechanical kriya is useless. Kalyana means
moral qualities. They too have spiritual value only if they are linked with feeling; then they help in the development of the
inner personality, enabling us to love God.
Ramanuja then speaks of anavasada and anuddharsha. Avasada or depression hinders spiritual life. Hence, it must be avoided. How? By cheerfulness, which means joyful tranquility — tranquility with the power of joyfully facing all difficulties and problems. Ramanuja calls it anuddharsha, joyfulness without excitement due to excessive elation. Otherwise, joy will be followed by a negative reaction; the sadhaka will become bahir mukha or extrovert, and lower impulses like lust and greed will arise. If the sadhaka puts these principles advocated by Ramanuja into practice, then his or her bhakti will be well grounded and stable.
Source - Excerpts from article titled 'Narada Bhakti Sutra' by Swami Bhaskareswarananda published in August 2008 edition of Prabuddha Bharata Magazine.