Vemana said that salt and camphor look alike but they taste so differently. Brass and gold look alike when we look at them but when we let them fall down, the sound they produce is very different.
In the same manner, when the aspect of Divinity takes a human form, we find that the actions of such a form and ordinary human beings are superficially the same. (SSB 1978, p. 85)
Why God should assume human form? Because that is the only way to incarnate the God within man. The Avatar takes the human form and behaves in a human way so that humanity can feel kinship with divinity. At the same time he rises to godly heights so that mankind also can aspire to reach God. The realization of indwelling God as the motivator of life is the task for which Avatars come in human form. (S&M, p. 236)
People cannot stand the Lord in superhuman form. It is only when the Lord comes in human body that people are able to approach Him and learn to love Him even a little bit. But one should not make the mistake of thinking that the Lord forgoes His powers on assuming human form. For instance, the aeroplane flying high in the sky descends to the airport. But one should not think that the plane is the ground machine because one sees it on the ground. Once it has taken on its load of passengers, it again zooms up high into the sky. In like fashion, although the Lord has made a landing here on the earth, so to speak, He is not limited by His human form. (AV, p. 61)
By mere human form one cannot be called a human being. It is only when that human form has got the divine qualities that derive from the fact that they are created by God that he will be entitled to be called a human being. (EL, p. 88)
This, My human form, encompasses every faith (Dharma) and every divine potency (Shakti) of every god. Whatever be the names, forms and powers that man attributes to God, belong only to Sathya Sai and none else. And all prayers and offerings to God reach Me only. I can demonstrate it beyond doubt. That is why in all My discourses I emphasise that Allah, Jesus, Jehovah,Rama,Krishna, Ishvara and Sai are all names which pertain, without any difference whatsoever, only to Me.
When God comes down to earth in human form, it is very difficult to see the reality of God in the outward form. Man compares the earthly appearance of the avatar with his own body and mistakenly concludes that the two are of the same level and type. To tell you the truth, even if the entire humanity makes concerted effort for a thousand years through the severest austerities, it cannot comprehend My true essentiality (nija tattva). If you win the grace of this power standing right before you bearing a holy name and form, you will soon achieve supreme realization. You are exceptionally fortunate in having this rare opportunity. It is far more precious than what eminent sages, renunciants, yogis, and holy men had ever got. Forget not this fact. (PraV, pp. 167-168)