CC Ādi 5.131

kṛṣṇa yabe avatare sarvāṁśa-āśraya
sarvāṁśa āsi’ tabe kṛṣṇete milaya
Word for word: 
kṛṣṇa — Lord Kṛṣṇa; yabe — when; avatare — descends; sarva-aṁśa-āśraya — the shelter of all other viṣṇu-tattvas; sarva-aṁśa — all plenary portions; āsi’ — coming; tabe — at that time; kṛṣṇete — in Kṛṣṇa; milaya — join.
Translation: 
When the Supreme Personality of Godhead Kṛṣṇa appears, He is the shelter of all plenary parts. Thus at that time all His plenary portions join in Him.