Gopalacampu 1.31.107

1.31.107

[80] atha purastād uddhava-darśana-mātreṇa ca te parama-sukhaṃ prāpsyanti | yataḥ-
aparicaye' py avalokād bhaktaṃ bhaktaḥ piparti kṛṣṇasya |
svaramātrāt tad-gānārambhaḥ sujanaṃ pramodayati ||

Then, at the mere sight of Uddhava before them, they will attain the highest joy. For: / Even without prior acquaintance, a devotee of Kṛṣṇa delights another devotee at the very sight; / the mere tune of the beginning of his song brings great joy to a virtuous person.