There is nothing called Hinduism just to make you correct on the point . It's Sanatana dharma . Sanatana dharma is vast as I agree with you and it's great but Sai is endless , infinite , greatest, no enough words to describe his quality ( nirgun parambramhan ) as per Veda. We can turn water of...
It's other way around my dear . Shiv is incarnation of Sai .. Sai is param Bramhan from whom trinity and million billion universe belong and at the end mingle into him.... He lives and spread himself in every particles, atoms , and molecules .. He is formless param Bramhan .. Shiva , Vishnu...