Arjuna asked, 'You spoke of Brahma (the Absolute), adhyatma, karma, adhibhuta, adhidaiva and adhiyajna, but I do not understand the meaning of all these words. Again you say that at the hour of death you are revealed to those who know you as adhibhuta, etc. and have attained evenness of temper. Please explain all this to me.'
The Lord replied, 'Brahma is the imperishable Supreme aspect of God, and adhyatma is the individual soul living in the body of all beings as the doer and the enjoyer. Karma is the process through which all beings come into existence, or in other words, the process of creation. Adhibhuta is Myself as the perishable body, and adhiyajna is the individual soul purified through sacrifice. Thus whether as the body or as the foolish soul or as the purified soul or as Brahma, it is I who am everywhere. And never doubt this that he who meditates on Me in all these aspects at the hour of death, forgets himself, is careful of nothing and desirous of nothing will be united with Me. Whatever a man constantly dwells on in his mind and remembers at the time of death is realized by him. Therefore at all times you should remember Me and set your mind and heart upon Me and you will surely come to Me. You may say that it is hard thus to stabilize the mind. But you take it from Me that one can become single-minded by daily practice and constant endeavour, for as I told you just now, all embodied beings are in the essence Myself in various forms. For this he should prepare himself from the very first so that his mind does not go astray at the time of death, but is steeped in devotion, keeps the life force (prana) steady, and thinks only of Me as the omniscient, the ancient, the ruler, the subtle supporter of all and dispeller of ignorance like the sun which drives darkness away.
'This supreme state is known to the Vedas as akshara (the Imperishable) Brahma and is reached by sages who have freed themselves from likes and dislikes. All who desire to reach it observe brahmacharya, i.e., keep body, mind and speech under control and give up all objects of sense in these three ways. Men and women who die, having controlled the senses and uttering the sacred syllable Om and remembering Me as they depart, reach the supreme state. Their mind is never distracted by other thoughts, and when they have thus come to Me, they are not reborn into this painful condition. To come to Me is the only means of breaking the vicious circle of birth and death.
'Men measure time by the human span of a hundred years, and during that period do thousands of questionable deeds. But time is infinite. A thousand yugas (ages) make up the day of Brahma; compared with it a human day or even a hundred years of human life are as nothing. What is the use of counting such infinitesimal measures of time? Human life is as only a moment in the infinite cycle of time. It is up to us therefore to think of God alone to the exclusion of all else. How can we afford to run after momentary pleasures? Creation and dissolution have gone on unceasingly during Brahma's day and night and will do so in future too.
'Brahma who creates and dissolves beings is only an aspect of Me. He is the unmanifested which cannot be perceived by the senses. Beyond this unmanifested there is yet another unmanifested aspect of Mine of which I have spoken to you. He who reaches it is not reborn, for there is no day or night so far as this is concerned. This is a calm and immovable aspect, which can be realized only by single-minded devotion. It supports and pervades the whole universe.
'It is said that one who dies in the bright half of the month during Uttarayana (the northward movement of the sun from January to July) comes to Me if he is mindful of Me at last, and that he' who dies in the dark half of the month during Dakshinayana (the southward movement from July to January) is reborn into the world. Uttarayana and the bright fortnight here may be interpreted to mean the path of selfless service; and Dakshinayana and the dark half of month mean selfishness. The path of service is the path of wisdom, and the path of selfishness is the path of ignorance. He who treads the path of wisdom is released from the bondage of birth and death while he who takes the path of ignorance becomes a bond-slave. After having realized the difference between the two, who would be so foolish as to prefer to walk in the way of ignorance? All men should learn to discriminate between the paths, renounce all fruits of merit, act in a spirit of detachment and discharge their duty with all their heart and soul, and thus endeavour to reach the supreme state described by Me.'