When the Asura Prahlāda had become identified with Vishnu by virtue of contemplation all the bonds were at once severed, as soon as he shook. The mighty deep rose up in waves and the monsters therein were terrified. And the earth trembled with all her mountains and forests. And throwing aside the pile of rocks that were placed by the Daityas on his breast, the high-minded Prahlāda came out of waters. And beholding the outer world, earth and heaven, he remembered who he was and knew himself to be Prahlāda.

In plain words: Prahlada, a boy born into the Asura (demon) family, had been tied up and thrown into the sea with rocks piled on him. Lost in thinking of Vishnu, he became one with him. When he stirred, his ropes broke, the sea and earth shook, and he pushed off the rocks and came out of the water. Then he looked around and remembered that he was Prahlada again.