Caitanya-caritāmṛta 5.154
sei aṁśa lañā jyeṣṭha-kaniṣṭhābhimāna aṁśāṁśi-rūpe śāstre karaye vyākhyāna
[sei amsha lanaa jyeshtha-kanishthaabhimaana amshaamshi-roope shaastre karaye vyaakhyaana]
Blended reading (Sanskrit + English inline)
sei aṁśa lañā jyeṣṭha-kaniṣṭhābhimāna aṁśāṁśi-rūpe śāstre karaye vyākhyāna
Kṛṣṇa and Balarāma present Themselves as younger brother and elder brother, but in the scriptures They are described as the original Supreme Personality of Godhead and His expansion.
My note
Source: vedabase.io