Bhikkhu Bodhi eloquently describes the importance of our relationships in an essay called “Association with the Wise” (http://www.accesstoinsight.org/lib/authors/bodhi/bps-essay_26.html). Here are a couple of paragraphs from that short piece:
Contrary to certain psychological theories, the human mind is not a hermetically sealed chamber enclosing a personality unalterably shaped by biology and infantile experience. Rather, throughout life it remains a highly malleable entity continually remolding itself in response to its social interactions. Far from coming to our personal relationships with a fixed and immutable character, our regular and repeated social contacts implicate us in a constant process of psychological osmosis that offers precious opportunities for growth and transformation. Like living cells engaged in a chemical dialogue with their colleagues, our minds transmit and receive a steady barrage of messages and suggestions that may work profound changes even at levels below the threshold of awareness. …
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.
Even if we feel like completely autonomous, independent beings, the osmosis between ourselves and our environment goes on without respite. We harbor many wholesome and unwholesome potentials, which rise up to meet stimuli similar to themselves, and which can wither if they don’t find a foothold in our hearts.
None of us is immune to the influence of the people and things around us. When I walk by a dessert display, something in me thrills to the sight. It’s rare that I’ll actually buy and eat one of those desserts, but the response is automatic and unmistakeable. I know, “This is what greed feels like.” A clear awareness of our responses can help protect us from our own selfish and harmful inclinations and help to move us in the direction of our better qualities.
We might have to look more carefully for the influences that feed our wholesome roots, as they tend to be more subtle. Anger and greed are immediately and powerfully felt whether they are our own or someone else’s. Kindness, calm, and wisdom are quieter qualities, and we might miss them if our radar is not out for them.
For now, we can examine the environment we live and move in, and imagine ways in which we can avoid or reduce harmful influences and bring closer those people and activities supportive of wholesome development. The resulting joy is a subtle but powerful and enduring feeling.