If one does not take to the path of disciplic succession, it is not possible for one to understand the Supreme Personality of Godhead. If one understands the Supreme Lord through devotional service with faith in the disciplic succession and then advances further, he awakens his natural love for God, and then his success in life is assured.- His Divine Grace A. C. bhaktivedanta Swami Prabhupada Srimad-Bhagavatam 7.7.17, Purport

Sins accumulated by words, actions, or the mind are removed only by remembering the Supreme Personality of Godhead, Lord Sri Krishna.- Brahma-vaivarta Purana Quoted in Hari-bhakti-vilasa (3.55)

Devotional service is the process of worshiping the Supreme Lord. It consists of fixing one’s mind upon Him by renouncing all material desires for enjoyment in this world and the next. Indeed, this is true renunciation.- Gopala-tapani Upanisad, Purva 15

because it is filled with pure transcendental knowledge, and because it is thus the best of all conclusions, the conclusion accepted by all noble-hearted and spiritually intelligent persons in all countries and at all times past, present, and future, and because it is the root from which all truths have come, devotional service is the highest truth, the conclusion better than all other conclusions.- Srila Bhaktivinoda Thakura, Tattva-sutra 48, Commentary

Devotional service is the supreme goal, the supreme wealth, the supreme abode, and the supreme bliss. all varieties of ecstasy arise from it.- Brhad-aranyaka Upanisad 4.3.32

an expert geologist can understand where there is gold and by various processes can extract it from the gold ore. Similarly, a spiritually advanced person can understand how the spiritual particle exists within the body, and thus by cultivating spiritual knowledge he can attain perfection in spiritual life.- Sri Prahlada Maharaja Srimad-Bhagavatam 7.7.21

The Lord is the master of matter and the jivas and is endowed with all good qualities.- Svetasvatara Upanisad 6.16

One should abandon all doubts and fear of the various philosophers who speak nonsense under the sway of their own karma and the force of time. One should then incessantly meditate upon Lord Hari, Krishna, who by His charming sweetness steals away the mind of those endowed with prema, pure love of God.- Srila Visvanatha Cakravarti Thakura Sarartha Darsini 10.87.50, Commentary