Those who understand simply that the living being is not matter but spirit soul and who desire to merge into the Supreme Spirit Soul are in the lowest transcendental position. Above them are the mystic yogis, who by meditation see within their hearts the four-handed Vishnu form of the Paramatma, or Supersoul. But persons who actually associate with the Supreme Lord, Krishna, are the highest among all transcendentalists.
His Divine Grace A.C. Bhaktivedanta Swami Prabhupada
Narada-bhakti-sutra 2, Purport
But those who worship Me, giving up all their activities unto Me and being devoted to Me without deviation, engaged in devotional service and always meditating upon Me, having fixed their minds upon Me, O son of Pritha—for them I am the swift deliverer from the ocean of birth and death.
Lord Sri Krishna
Only the purified soul can attain the perfection of associating with the Personality of Godhead in complete bliss and satisfaction in his constitutional state. Whoever is able to renovate such devotional perfection is never again attracted to this material world, and he never returns.
In this lifetime one experiences a succession of sufferings, and in the next life one is likely to experience another unbearable series of sufferings. Hearing this truth from the scriptures, an intelligent person will yearn to leave the world of birth and death.
Gopala Bhatta Goswami
O my Lord, may I have the association of Your devotees. Association with them is a sharp sword that cuts the bonds of repeated birth and death. Association with them is the only way to attain a place at Your lotus feet. Please give me devotional service to Your lotus feet birth after birth.
Brahma-vaivarta Purana 4.6.24
Bhakti , devotional service, leads the living entity to the Lord and enables him to see the Lord, who is controlled by bhakti. Bhakti is best of all.
Quoted by Madhvacharya in his commentary on Vedanta-sutra 3.3.53
Wherever propagation of Krishna’s names and topics is lacking, there will be temple ceremonies based on solitary worship devoid of preaching, external performances of sacrifice, and the process of meditation and remembrance based on solitary worship. The Supreme Lord, Sri Krishna Chaitanya, established the superiority of nama-sankirtana [chanting the holy names] over the three processes of the previous ages.
Srila Bhaktisiddhanta Sarasvati Thakura
Chaitanya-bhagavata, Ådi-khanda 14.133, Commentary