In plain words
There is One alone: ‘the one Ātma, the Ātma within all beings’. Though forms and names are many, Śrī Rāma is that very oneness present in them all. He Himself took on the forms of cattle, birds and wild beasts too. Apart from Him alone, I see no other creature at all in this world. Not a beast, not a bird: nothing at all is seen. That very principle of the one Ātma has the name ‘Hiraṇyagarbha’.
As desires grow, God moves away
In the Tretā age Sītā too incarnated with Śrī Rāmacandra, to teach women the principle of the faithful wife. Though she spent fourteen years living in the forest, though she stayed ten months in Laṅkā, whatever the circumstances she remained of one mind. To be near Rāma, she left her all behind in Ayodhyā and came to the forest at Rāma's side. Such a Sītā wished for a golden deer. When that desire arose, then Rāma moved away from her. That is, as desires grow, God keeps moving away from us. Less luggage, more comfort makes travel a pleasure. So we must cut down the ‘luggage’ of desires. Sītā knew that a golden deer cannot exist in this world. But, true to her part in the Rāmāyaṇa, to teach her principle to the world, she asked to have that golden deer. Because of that desire she was parted from Rāma and suffered greatly.
The ordeal by fire, to show the ideal
In the Aśoka grove Sītā gave up sleep and food and dwelt without a break on the Rāma principle alone. Night and day she had no thought but the thought of Rāma. Even so, when Rāma took her back, he made her pass through the ordeal by fire. What for? Only to proclaim her ideal to the world. Then the Fire-god himself appeared: “Rāmacandra! Sītā is a wife of great fidelity. She dwells on nothing but Your Name,” he said.