Krsna is the supreme father, and all living entities within the material world are exactly like misled children of a wealthy man who have left home to loiter in the street. Therefore the greatest benefit one can bestow upon one's fellow human being is to give him Krsna consciousness.
His Divine Grace A.C. Bhaktivedanta Swami Prabhupada
Teachings of Queen Kunti, p. 14
Persons who are impelled by pure devotional service in Krsna consciousness and who therefore go to see the Deities of Visnu in the temple will surely get relief from entering again into the prison of a mother's womb.
Hari-bhakti-sudhodaya
Those who are actually advanced in knowledge are able to appreciate the essential value of this age of Kali. Such enlightened persons worship Kali-yuga because in this fallen age all perfection of life can easily be achieved by the performance of sankirtana, the congregational chanting of the Lord's holy names.
Sri Karabhajana Muni
Srimad-Bhagavatam 11.5.36
From association with devotees is born faith. From faith is born pure knowledge. From pure knowledge is born meditation. From meditation is born devotional service, which pleases Lord Krsna and destroys all sufferings.
Srila Bhaktivinoda Thakura
Sri Datta-kaustubha, Text 30
One may cleanse himself daily by taking a bath in water, but if one takes a bath even once in the sacred Ganges water of Bhagavad-gita, for him the dirt of material life is altogether vanquished.
Gita-mahatmya 3
Anyone who has developed the ecstasy of love for the Supreme Personality of Godhead, and who is always merged in transcendental bliss on account of that love, cannot even perceive the material happiness or distress coming from the body or mind.
Lord Siva
Narada-pancaratra
Within the heart of a person overpowered by lamentation or anger, there is no possibility of Krsna's being manifest.
Padma Purana