In the legend of Shakyamuni Buddha he continued to sit after his awakening. His post awakening experience was needed to determine what he would do next. Here it is central that he is human.
In the Vedas, existence was parsed into hell, hungry ghosts, animal, asuras, human, and deva realms. Transmigration from one realm to another was theologically possible after death. But now something rare had occurred in the cosmos, a human had awakened, Shakyamuni being the seventh. This meant that a human had seen into the meaning of the great mystery of birth and death as only a few others had done before Shakyamuni.
So, Brahma, as a Deva, saw this and was pleased, but why? If using the logic of the Vedas we are locked in our realm until death, then the only realm that can make use of impermanence in the moment is human. This means this Buddha had the potential to share the way of enlightenment to others. Human's could then learn to address suffering. The only catch was getting the new Buddha to teach. D.T. Suzuki points to this as a pivotal moment in human history. He is saying the only way for humans to end suffering is to have a human complete this transformation within his/her life time and then use it to teach others. This is a huge breakthrough that would be contained to just one person if that way was not shared, not taught.
In the hierarchy of Devas they need human's to intervene (they can whisper) and here one could say Buddha was between human (say a Human+) and Deva. So Brahma seeing this asked Shakyamuni to teach humans how to do what he had done. Three times the legend says he asked and the first and second responses were- I am not worthy. It was only through the diligence of Brahma, and the third ask that the meaning of Bodhisattva emerged. One could suggest that this was a second and more profound awakening. Shakyamuni Buddha must have realized...If I can help others get what I have, it may be possible for all humans to penetrate the great mystery.
Buddha said he vowed to teach and we say we vow to follow the Buddha's teachings. Okumura-Roshi in his book Living By Vow, says Buddha's vowed to teach was opening the Dharma gate of diligence to save all beings, to end all delusions, to open all truths (Dharma Gates) by a way of life that is unsurpassable-The Buddha Way.
This is the beginning of the unsurpassed profound and wondrous Dharma being made available. Our ancestors have been turning the wheel of Dharma and sharing across so we can see, hear, accept and maintain it.
Right now right here we vow to hand it to the next person...
May all beings be awakened...