I have already described, my body, your body, has a history of janma, or birth, a date of birth. So janma ādi means birth and sustenance and death. We have got this body produced, or born, at a certain date. It keeps, sustains, for a certain period—say fifty years, sixty years or a hundred years, utmost—and then again it is destroyed.
Therefore janma ādi means birth is also coming from Him, maintained also by Him, and when it is destroyed, it goes unto Him. That is called janma ādi, means birth, maintenance and annihilation. Janmādy asya. All this material world, they are undergoing the same process: janma, sustenance and end. Everything. This universe also is like that, everything, even the ant's body or my body, your body, elephant's body, or there are many demigods' body. Just like we have learned from Bhagavad-gītā, Brahmā's body, it keeps for millions and millions of years. One day we cannot calculate.
So there are different types of bodies within this material world. We can compare. Just like ant's body, a fly's body and my body. A fly's body may remain for few years, eh, few hours. So our body may remain for few years. And similarly, there are other living entities like Brahmā, their body remains for few decades. But every body, each body, is subjected to this law of nature: birth, death, disease and old age.
So God's body is not like that. It is eternal. Here in this material world we can possess a body which may exist for millions of years, but that does not mean it is eternal. It is not eternal. But God's body is eternal. Therefore, in the Vedic language, when it is said nirākāra—nirākāra means "Who has no form"—it does not mean that God has no form. He has got form, but His form is different from this form upon which you have got experience.