Srimad-Bhagavatam: Canto 11 - Chapter 1 - Verse 9
Sanskrit:
अर्चायां स्थण्डिलेऽग्नौ वा सूर्ये वाप्सु हृदि द्विज: ।द्रव्येण भक्तियुक्तोऽर्चेत् स्वगुरुं माममायया ॥ ९ ॥
ITRANS:
arcāyāṁ sthaṇḍile ’gnau vāsūrye vāpsu hṛdi dvijaḥdravyeṇa bhakti-yukto ’rcetsva-guruṁ mām amāyayā
Translation:
A twice-born person should worship Me, his worshipable Lord, without duplicity, offering appropriate paraphernalia in loving devotion to My Deity form or to a form of Me appearing upon the ground, in fire, in the sun, in water or within the worshiper’s own heart.