In plain words
And he says he will take Rāma off to the forest to guard the yajña! Rāma has never gone to the forest, never seen demons, never fought with anyone. He has hatred for no one. How can I send such a one to the forest?” he thought to himself, and then: “Best of ṛṣis! How can I send Rāma, a little boy, to fight with demons?” he said. At once Viśvāmitra: “Daśaratha! In your Ikṣvāku line, no one until now has gone back on his word. If you go back on your word now, you will be the one who brought disgrace on the Ikṣvāku line itself. So, will you send Rāma with me? Or will you go back on your word? Think it over,” he said. Unable to decide anything, Daśaratha sent for Vasiṣṭha. He: “Daśaratha! Your sons are no ordinary men; they are boons granted to you by the will of God; suns of Jñāna born out of the fire. No danger of any kind will befall them. So, as you gave your word, send Rāma with Viśvāmitra,” he persuaded him.
Here you must recognise one important thing. Viśvāmitra asked for Rāma alone. Rāma set out with him. When He was leaving, Rāma did not call Lakṣmaṇa to come with Him; His father did not order him to go, nor did Viśvāmitra ask him to come. Yet, as a reflection goes with its image, Lakṣmaṇa too set out with Rāma. For he was of Rāma's portion. Viśvāmitra took it to be the will of God. Before he went, to Daśaratha: “Daśaratha! There is no power that is not in me. But while I sit under the vow of the yajña, I must not take up violence; I must not kill, even demons. That is the rule that goes with the vow of the yajña. That is why I asked you to send Rāma with me,” he said.
The three reached the bank of the Sarayū. ‘Rāma, come here,’ Viśvāmitra called.