Wisdom from the Bhagavad Gita 28

23. But the fruit accruing to these men of little understanding is limited. The worshippers of the Devas go to the Devas; My devotees too come to me.

24. The foolish regard Me, the un-manifested, as come into manifestation, not knowing My supreme state—immutable and transcendental.

25. Veiled by the illusion born of the congress of the Gunas, I am not manifest to all. This deluded world knows Me not, the Unborn, the Immutable.

26. I know, O Arjuna, the beings of the whole past, and the present, and the future, but Me none know.

27. By the delusion of the pairs of opposites, arising from desire and aversion, O descendant of Bharata, all beings fall into delusion at birth, O scorcher of foes.

28. Those men of virtuous deeds, whose sin has come to an end—they, freed from the delusion of the pairs of opposites, worship Me with firm resolve.

29. Those who strive for freedom from old age and death, taking refuge in Me, they know. Brahman, the whole of Adhyâtma (Supreme Self), and Karma in its entirety.

30. Those who know Me with the Adhibhuta (Physical), the Adhidaiva (Spiritual), and the Adhiyajna (Divine), continue to know Me even at the time of death, steadfast in mind. 

—Bhagavad Gita, 7:23-30