Bhagavad Gita · 18.69

न च तस्मान्मनुष्येषु कश्चिन्मे प्रियकृत्तमः।भविता न च मे तस्मादन्यः प्रियतरो भुवि॥

na cha tasmān manuṣhyeṣhu kaśhchin me priya-kṛittamaḥ bhavitā na cha me tasmād anyaḥ priyataro bhuvi

There is none among human beings who does dearer service to Me than such a one, nor shall there be another on earth dearer to Me.

— Bhagavad Gita 18.69

Source: Sacred-Texts.com (Sanskrit) + Bhagavad-Gita.io (translations)