The Buddha was born as a human being. During his life as a human being he realised by his own practice - in the last resort without a teacher - the highest deliverance of suffering (Enlightenment/Nirwana). He never spoke on behalf of (or in service of) another (higher) being. He always referred to the potentials his attendants might realise by their own practice. Step by step, but every step can be a deliverance on its own. At the end of his life the Buddha appointed the Dhamma, his teachings/instructions, as his successor. In this link you will find expositions of the Buddha-Dhamma by contemporary teachers who practice this teaching.