The Lord counsels: “Do not associate with unbelieving materialists.”
The spiritual being who has received a human body, which is in itself more conducive to the realization of the Supreme Person, and who has placed himself in the duties of service of love and devotion to the Lord becomes capable of realizing it, He who is the very identity of spiritual bliss. Such a living being, entirely dedicated to Krishna, the Supreme Person, is freed from the influence of Maya. Even if he continues to reside in this world created by the illusion, he is completely unaffected by it. On the other hand, unbelieving materialistic incarnated souls, bound by Maya (the energy of illusion), are devoted only to their bellies and genitals. They are impure, and by associating with them they will fall into the dark pit of ignorance.
He who is intelligent must renounce bad associations and not associate himself with unbelieving materialistic people, but on the other hand, let himself be attracted by holy beings, great souls. By their transcendental instructions, the holy devotees of the Lord can break the false attachments of their minds. True saints are always liberated and consecrated to the Supreme Person.
Krishna, God, the Supreme Person says:
Having attained this form of human life [the Lord speaks of a soul that has been incarnated into a human body], which gives the opportunity to know Me, and being situated in My devotional service, I can be realized as the reservoir of all pleasure and the Supreme Soul of all existence, residing in the heart of every living being. A person frozen in transcendental knowledge is freed from conditioned life by renouncing his false identification with the attributes and modes of influence of material nature; virtue, passion, and ignorance. Considering these attributes and modes of influence of the material nature as a mere illusion, it (the incarnate soul) avoids tangling with them. Because the attributes and modes of influence of material nature are simply not real, it does not accept them.
One should never associate with materialists, those who are dedicated to satisfying their genitals and bellies. By following them, one falls into the deepest darkness, just like a blind man following another blind man. An intelligent person must reject all evil association and instead resume union with the holy devotees (the holy servants of God), whose words cut off the excessive attachment of the mind. My faithful devotees fix their minds on Me and are not dependent on anything material. They are always peaceful, endowed with equal vision and free from possession, false ego, duality and greed. In union with these holy devotees there is constant discussion of Me, and those who partake in this singing and hearing of My glories are certainly cleansed from all their sins.