SB 1.3.35

evaṁ janmāni karmāṇi
 hy akartur ajanasya ca
varṇayanti sma kavayo
 veda-guhyāni hṛt-pateḥ
Synonyms: 
evam — thus; janmāni — birth; karmāṇi — activities; hi — certainly; akartuḥ — of the inactive; ajanasya — of the unborn; ca — and; varṇayanti — describe; sma — in the past; kavayaḥ — the learned; veda-guhyāni — undiscoverable by the Vedas; hṛt-pateḥ — of the Lord of the heart.
Translation: 
Thus learned men describe the births and activities of the unborn and inactive, which is undiscoverable even in the Vedic literatures. He is the Lord of the heart.
Purport: 

Both the Lord and the living entities are essentially all spiritual. Therefore both of them are eternal, and neither of them has birth and death. The difference is that the so-called births and disappearances of the Lord are unlike those of the living beings. The living beings who take birth and then again accept death are bound by the laws of material nature. But the so-called appearance and disappearance of the Lord are not actions of material nature, but are demonstrations of the internal potency of the Lord. They are described by the great sages for the purpose of self-realization. It is stated in the Bhagavad-gītā by the Lord that His so-called birth in the material world and His activities are all transcendental. And simply by meditation on such activities one can attain realization of Brahman and thus become liberated from material bondage. In the śrutis it is said that the birthless appears to take birth. The Supreme has nothing to do, but because He is omnipotent, everything is performed by Him naturally, as if done automatically. As a matter of fact, the appearance and disappearance of the Supreme Personality of Godhead and His different activities are all confidential, even to the Vedic literatures. Yet they are displayed by the Lord to bestow mercy upon the conditioned souls. We should always take advantage of the narrations of the activities of the Lord, which are meditations on Brahman in the most convenient and palatable form.