CC Madhya 19.205
babandha prākṛtaṁ yathā
tam — Him (Kṛṣṇa); matvā — considering; ātmajam — own son; avyaktam — unmanifested; martya-liṅgam — manifested as if perishable; adhokṣajam — beyond the perception of the senses; gopikā — mother Yaśodā; ulūkhale — to the mortar; dāmnā — with rope; babandha — bound; prākṛtam — an ordinary child; yathā — like.
“ ‘Although Kṛṣṇa is beyond sense perception and is unmanifest to human beings, He takes up the guise of a human being with a material body. Thus mother Yaśodā thought Him to be her son, and she bound Lord Kṛṣṇa with rope to a wooden mortar, as if He were an ordinary child.’
This verse from Śrīmad-Bhāgavatam (10.9.14) is in reference to Lord Kṛṣṇa’s exhibiting Himself like an ordinary child before mother Yaśodā. He was playing like a naughty boy, stealing butter and breaking butter pots. Mother Yaśodā became disturbed and wanted to bind the Lord to a mortar used for pounding spices. In other words, she considered the Supreme Personality of Godhead an ordinary child.