A perspective from the Buddha's Teachings:
''Particularly critical to our spiritual progress is our selection of friends and companions, who can have the most decisive impact upon our personal destiny. It is because he perceived how susceptible our minds can be to the influence of our companions that the Buddha repeatedly stressed the value of good friendship (kalyanamittata) in the spiritual life. The Buddha states that he sees no other thing that is so much responsible for the arising of unwholesome qualities in a person as bad friendship, nothing so helpful for the arising of wholesome qualities as good friendship (AN 1.vii,10; I.viii,1). Again, he says that he sees no other external factor that leads to so much harm as bad friendship, and no other external factor that leads to so much benefit as good friendship (AN 1.x,13,14). It is through the influence of a good friend that a disciple is led along the Noble Eightfold Path to release from all suffering (SN 45:2).
Good friendship, in Buddhism, means considerably more than associating with people that one finds amenable and who share one's interests. It means in effect seeking out wise companions to whom one can look for guidance and instruction. The task of the noble friend is not only to provide companionship in the treading of the way. The truly wise and compassionate friend is one who, with understanding and sympathy of heart, is ready to criticize and admonish, to point out one's faults, to exhort and encourage, perceiving that the final end of such friendship is growth in the Dhamma. The Buddha succinctly expresses the proper response of a disciple to such a good friend in a verse of the Dhammapada: "If one finds a person who points out one's faults and who reproves one, one should follow such a wise and sagacious counselor as one would a guide to hidden treasure" (Dhp. 76).
Association with the wise becomes so crucial to spiritual development because the example and advice of a noble-minded counselor is often the decisive factor that awakens and nurtures the unfolding of our own untapped spiritual potential. The uncultivated mind harbors a vast diversity of unrealized possibilities, ranging from the depths of selfishness, egotism and aggressivity to the heights of wisdom, self-sacrifice and compassion. The task confronting us, as followers of the Dhamma, is to keep the unwholesome tendencies in check and to foster the growth of the wholesome tendencies, the qualities that lead to awakening, to freedom and purification. However, our internal tendencies do not mature and decline in a vacuum. They are subject to the constant impact of the broader environment, and among the most powerful of these influences is the company we keep, the people we look upon as teachers, advisors and friends. Such people silently speak to the hidden potentials of our own being, potentials that will either unfold or wither under their influence.''
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