Why is Sai Baba's life story described as 'incomprehensible and marvelous'?

Sai Baba's life is described as 'incomprehensible and marvelous' because His actions and state of being were beyond ordinary understanding. As Chapter 37 of the Shri Sai Satcharitra explains, He existed in an unpredictable state, sometimes absorbed in the bliss of the Self (Brahmananda), and at other times performing actions while remaining completely detached. He was always alert in His true form, yet appeared deep and profound, like an ocean that is difficult to fathom. The text notes that those who tried to search for the cause behind His actions would eventually become exhausted and sit in quiet amazement, unable to grasp the true depth of His unfathomable form, as highlighted in Chapter 37.