In plain words
By the divine power of the Name of Rāma the stones did not sink but floated up; yet, struck by the waves, each stone began to drift off in a different direction. Only if all the stones joined one another would a causeway be formed, would it not! So instead of writing ‘Rāma’ on one stone, the monkeys wrote ‘Rā’ on one and ‘Ma’ on another, and threw them into the sea with Bhakti and śraddhā. Then, instead of drifting off this way and that, the stones all joined one another and formed a bridge.
Only the Name keeps you from sinking!
What held those stones up on the water? The Name of Rāma! Those two syllables, ‘Rāma’, alone held the stones up on the water. It was on that bridge made of the Name that Rāma went to Laṅkā and slew Rāvaṇa. In this way Rāma taught then that the Name alone is true, the Name alone is eternal. All forms grow old and at last perish. Forms must sink, on some day, at some time, in some place! Wherever you go, the Name alone keeps you from sinking! That alone is everlasting. No one can spoil the Name, or destroy it, or take it away from you. Vibhīṣaṇa too, who helped Rāma, said, ‘Rāma! Your Name alone has achieved everything.’ So it is enough to remember the Name of Rāma; we will have victory in every way. The Name of Rāma, of Kṛṣṇa, of Śiva, of Hari, of Hara: all these are Names of two syllables. If you take them as your support, you can achieve any great deed at all. So you must remember the Name of God without ceasing.
I am easily won by remembering the Name alone
However many gifts of charity, however many yajñas and yāgas you perform, you do them all only for a passing satisfaction of the mind. Bhakti is of nine kinds.