SB 10.10.39
sri-suka uvaca
ittham sankirtitas tabhyam
bhagavan gokulesvarah
damna colukhale baddhah
prahasann aha guhyakau
Translation by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Sukadeva Gosvami continued: The two young demigods thus offered prayers to the Supreme Personality of Godhead. Although Sri Krsna, the Supreme Godhead, is the master of all and was certainly Gokulesvara, the master of Gokula, He was bound to the wooden mortar by the ropes of the gopis, and therefore, smiling widely, He spoke to the sons of Kuvera the following words.
Purport by His Divine Grace A. C. Bhaktivedanta Swami Srila Prabhupada:
Krsna was smiling because He was thinking to Himself, “These two young demigods fell from the higher planetary system to this planet, and I have delivered them from the bondage of standing for a long time as trees, but as for Me, I am bound by the ropes of the gopis and am subject to their chastisements.” In other words, Krsna submits to being chastised and bound by the gopis because of pure love and affection worthy of being praised by a devotee in so many ways.