This process entails always considering oneself the eternal servant of Krsna, making friends with Him and dedicating everything unto Him. These nine items of devotional service, when directly offered to Krsna, constitute the highest attainment of life

Expressions researched:
"always considering oneself the eternal servant of Kṛṣṇa, making friends with Him and dedicating everything unto Him. These nine items of devotional service, when directly offered to Kṛṣṇa, constitute the highest attainment of life"

Sri Caitanya-caritamrta

CC Madhya-lila

“‘This process entails hearing, chanting and remembering the holy name, form, pastimes, qualities and entourage of the Lord, offering service according to the time, place and performer, worshiping the Deity, offering prayers, always considering oneself the eternal servant of Kṛṣṇa, making friends with Him and dedicating everything unto Him. These nine items of devotional service, when directly offered to Kṛṣṇa, constitute the highest attainment of life. This is the verdict of the revealed scriptures.’.

CC Madhya 9.259-260, Translation and Purport

“‘This process entails hearing, chanting and remembering the holy name, form, pastimes, qualities and entourage of the Lord, offering service according to the time, place and performer, worshiping the Deity, offering prayers, always considering oneself the eternal servant of Kṛṣṇa, making friends with Him and dedicating everything unto Him. These nine items of devotional service, when directly offered to Kṛṣṇa, constitute the highest attainment of life. This is the verdict of the revealed scriptures.’

Śrī Caitanya Mahāprabhu quoted these verses from Śrīmad-Bhāgavatam (SB 7.5.23-24).