By the mercy of the Lord even a layman can compose prayers of the highest spiritual perfection. Such spiritual perfection is not limited by material qualifications but is developed by dint of one's sincere endeavor to render transcendental service. Voluntary endeavor is the only qualification for spiritual perfection.
His Divine Grace A. C. Bhaktivedanta Swami Prabhupada
Srimad-Bhagavatam 3.9.38, Purport
The holy name of Krsna is the sweetest of the sweet, the most auspicious of the auspicious. This transcendental fruit of all the Vedas is purely spiritual. Whoever chants it but once, whether with faith or with contempt, is liberated.
Skanda Purana, Prabhasa-khanda
Persons who are very expert and most intelligent in understanding things as they are engage in hearing narrations of the auspicious activities and pastimes of the Lord, which are worth chanting and worth hearing. Such persons do not care even for the highest material benediction, namely liberation, to say nothing of other less important benedictions like the material happiness of the heavenly kingdom.
The Four Kumaras
Srimad-Bhagavatam 3.15.48
O Lord, only those devotees who have completely surrendered unto You are able to see Your opulence continuously, although you hide Yourself by Your yoga-maya. Your opulence is beyond time, space, and any material object, and there is nothing equal or superior to it.
Sri Yamunacarya
Stotra Ratna 13
Any activities sanctioned in the revealed scriptures and aiming at the satisfaction of the Supreme Personality of Godhead are accepted by saintly teachers as the regulative principles of devotional service. If one regularly executes such service unto the Supreme Personality of Godhead under the direction of a bona fide spiritual master, then gradually he rises to the platform of serving in pure love of God.
Sri Narada Muni
Narada-pancaratra
People may say that there are many qualified people in this world with tasteful pastimes and jewellike opulences, but the best of beautiful sages have ascertained that Krsna, the prince of Vraja, is the only source of all this.
Krsnadasa Kaviraja Gosvami
Govinda-lilamrta