As long as a person is fully in cooperation with the wishes of the Lord, guided by the bona fide brahmanas and Vaishnavas and strictly following religious principles, one has no cause for despondency, however trying the circumstances of life.
His Divine Grace A. C. Bhaktivedanta Swami Prabhupada
Srimad-Bhagavatam 1.9.12, Purport

Pure devotees manifest spiritual bodily symptoms of ecstatic love simply by remembering and reminding others of the Supreme Personality of Godhead, Hari, who takes away everything inauspicious from the devotee. This position is attained by rendering devotional service according to the regulative principles and then rising to the platform of spontaneous love.
Lord Sri Krishna
Srimad-Bhagavatam 11.3.31, quoted in Sri Chaitanya-charitamrita, Madhya-lila 25.140

In all revealed scriptures, beginning with the Vedas, the central point of attraction is Krishna. When complete knowledge of Him is realized, the bondage of maya, the illusory energy, is automatically broken.
Sri Chaitanya Mahaprabhu
Sri Chaitanya-charitamrita, Madhya-lila,20.144

The one Supreme Lord lives hidden inside all created things. He pervades all matter and sits within the hearts of all living beings. As the indwelling Supersoul, He supervises their material activities. Thus, while having no material qualities Himself, He is the unique witness and giver of consciousness.
Svetashvatara Upanishad 6.11

The names of this world are not different from Him. All names in this world are names of the Supreme Personality of Godhead. All names refer to Him, Lord Vishnu, whom the wise declare is the Supreme Personality of Godhead.

May we always fix our hearts on Lord Krishna, who is the final goal taught by all the Vedas, who is the master of unlimited and inconceivable transcendental potencies, who is the Supreme Personality of Godhead, and who in His own pastimes creates, maintains, and destroys the material universes.
Srila Baladeva Vidyabhushana
Commentary on Vedanta-sutra 1.4.28

Who is that person without whom the living entities cannot feel happiness? That is the Supreme Personality of Godhead, who delights the individual spirit souls.
Taittiriya Upanishad 2.7

The residents of Vaikuntha transcend everything material. For persons within the material creation, the manifold glories of those residents and the glories of the Vaikuntha world and its master are beyond analogy and beyond the power of words to describe.
Sri Gopa-kumara
Sri Brihad-bhagavatamrita 2.4.40–41

My dear child, continue dancing, chanting, and performing sankirtana in association with devotees. Furthermore, go out and preach the value of chanting krishna-nama, for by this process You will be able to deliver all fallen souls.
Srila Ishvara Puri to Sri Chaitanya Mahaprabhu
Sri Chaitanya-charitamrita, Adi-lila 7.92