Vaishnava Samhita. Shri Surdas Charitam. Vol III Book VII Chp 5 Shloka 42

बर्हायिते ते नयने मुरारेर्दर्शनं विना |

दृष्टिस्तु सफला सैव यया कृष्णो विलोक्यते ||

The eyes that do not get the darshan of Shri Krishna are equal to the mere plumes of the peacock. Only those eyes that gain the darshan of Shri Krishna become useful.