There is a well known principle in biology: function follows form. For example, the double helical shape of DNA is essential for replication and expression of genes into proteins. The three dimensional shape of enzymes allows them to bind to their substrates with high specificity, and convert substrates to products. The spiral shape of the cochlea is essential for hearing. The eyes have a pupil and a white cornea with the retina at the back collecting photons that conduct nerve impulses to the brain. Specialized cells produce hair on the head, but not of the same size all over the body for a biological reason. Sharp teeth enable crushing and chewing by applying muscle forces on a small area. Stiff bones enable the balancing of compressive loads, and muscle fibers allow generation of tension. The shape, structure, and spatial location of every part of the body has a reason.
Now Kṛṣṇa’s body is not made of matter and his senses can do functions of all other senses. Yet his body is identically similar in terms of its parts to a human body. Is there no reason that his eyes have a pupil, or that his fingers have nails, or that his hands have five fingers with a little finger and a thumb? It seems that his organs, at least externally, have similar functions and features as humans, and that function mostly follows form even in his case. Would his form imply that Kṛṣṇa has the ‘spiritual equivalent’ of neurons or a brain? Does he possess a skull?
I posed such a question to Sri Babaji, and here is his answer.
“To understand it, we need to understand that Kṛṣṇa is a spiritual human being. He does nara-līlā. He relates with humans on earth in nara-līlā. If his body will be different, then there will be no more nara-līlā. So His body appears exactly like human body but it does not have the same purpose as our bodily limbs have. That is the meaning of līlā. He is not hungry like us but becomes hungry out of love. His body does not have blood flowing in it like us but in līlā he can show that. In other words His body appears exactly like a human and functions like it, but because it has to do such a function. His function and form are not related as is in our case. Our body is made (or has evolved, which ever you believe in) similar to His body in appearance only. This is the highest evolution possible. Human body will not evolve into something superior no matter how much climate change may occur. Kṛṣṇa has his appearance as a human being because love manifests highest in this form. All his limbs are manifestations for the sake of love, to reciprocate in love with His devotees. All other species also exist for this purpose only. So your theory of “function follows form” is opposite in Goloka – “form follows function”.”
So one may wonder: what is Kṛṣṇa’s body made of? The answer is that it is made of love or prema. We are used to thinking of prema as an emotion, or quality, but prema is also a substance. Indeed, in sāṅkhya, emotion or thought is considered a substance, because it is a state (vrtti) of the mind which is a substance (dravya). Because prema is a dravya, Kṛṣṇa’s body can be made of prema.
It is for this reason that one must first get bhāva or love for Kṛṣṇa. Then this bhāva will become the cause of achieving a specific spiritual form. One must aspire for bhāva (which we have defined and discussed in some detail on this site), instead of aspiring for some specific form like a mañjarī. Because, the form will not bring prema. In the spiritual world, form follows function. This is true of everyone- including Kṛṣṇa’s associates