Gita Chapter 8.16 to 8.20

Aabrahmabhuvanaallokaah punaraavartino’rjuna;
Maamupetya tu kaunteya punarjanma na vidyate.
16. (All) the worlds, including the world of Brahma, are subject to return again, O Arjuna! But he who reaches Me, O son of Kunti, has no rebirth!

Sahasrayugaparyantam aharyad brahmano viduh;
Raatrim yugasahasraantaam te’horaatravido janaah.
17. Those who know the day of Brahma, which is of a duration of a thousand Yugas (ages), and the night, which is also of a thousand Yugas’ duration, they know day and night.

Avyaktaadvyaktayah sarvaah prabhavantyaharaagame;
Raatryaagame praleeyante tatraivaavyaktasamjnake.
18. From the unmanifested all the manifested (worlds) proceed at the coming of the “day”; at the coming of the “night” they dissolve verily into that alone which is called the unmanifested.
COMMENTARY: Coming of the “day’ is the commencement of creation. Coming of the “night” is the commencement of dissolution.

Bhootagraamah sa evaayam bhootwaa bhootwaa praleeyate;
Raatryaagame’vashah paartha prabhavatyaharaagame.
19. This same multitude of beings, born again and again, is dissolved, helplessly, O Arjuna, (into the unmanifested) at the coming of the night, and comes forth at the coming of the day!

Parastasmaat tu bhaavo’nyo’vyakto’vyaktaatsanaatanah;
Yah sa sarveshu bhooteshu nashyatsu na vinashyati.
20. But verily there exists, higher than the unmanifested, another unmanifested Eternal who is not destroyed when all beings are destroyed.
COMMENTARY: Another unmanifested Eternal refers to Para Brahman, which is distinct from the unmanifested (primordial Nature), and which is of quite a different nature. It is superior to Hiranyagarbha (the creative Intelligence) and the unmanifested Nature because It is their cause. It is not destroyed when all beings from Brahma down to a blade of grass are destroyed.

Gita Chapter 8.05 to 8.10

giYam yam vaapi smaran bhaavam tyajatyante kalevaram;
Tam tamevaiti kaunteya sadaa tadbhaavabhaavitah.
6. Whosoever at the end leaves the body, thinking of any being, to that being only does he go, O son of Kunti (Arjuna), because of his constant thought of that being!
COMMENTARY: The most prominent thought of one’s life occupies the mind at the time of death. It determines the nature of the body to be attained in the next birth.

Tasmaat sarveshu kaaleshu maamanusmara yudhya cha;
Mayyarpitamanobuddhir maamevaishyasyasamshayam.

7. Therefore, at all times remember Me only and fight. With mind and intellect fixed (or absorbed) in Me, thou shalt doubtless come to Me alone.

Abhyaasayogayuktena chetasaa naanyagaaminaa;
Paramam purusham divyam yaati paarthaanuchintayan.
8. With the mind not moving towards any other thing, made steadfast by the method of habitual meditation, and constantly meditating, one goes to the Supreme Person, the Resplendent,

O Arjuna!
Kavim puraanamanushaasitaaram
Anoraneeyaamsam anusmaredyah;
Sarvasya dhaataaram achintyaroopam
Aadityavarnam tamasah parastaat.
9. Whosoever meditates on the Omniscient, the Ancient, the ruler (of the whole world), minuter than an atom, the supporter of all, of inconceivable form, effulgent like the sun and beyond the darkness of ignorance,

Prayaanakaale manasaachalena
Bhaktyaa yukto yogabalena chaiva;
Bhruvormadhye praanamaaveshya samyak
Sa tam param purusham upaiti divyam.
10. At the time of death, with unshaken mind, endowed with devotion and by the power of Yoga, fixing the whole life-breath in the middle of the two eyebrows, he reaches that resplendent Supreme Person.

Gita Chapter 2.36 to 2.40

Avaachyavaadaamshcha bahoon vadishyanti tavaahitaah;
Nindantastava saamarthyam tato duhkhataram nu kim.
36. Thy enemies also, cavilling at thy power, will speak many abusive words. What is more painful than this!

Hato vaa praapsyasi swargam jitwaa vaa bhokshyase maheem;
Tasmaad uttishtha kaunteya yuddhaaya kritanishchayah.
37. Slain, thou wilt obtain heaven; victorious, thou wilt enjoy the earth; therefore, stand up, O son of Kunti, resolved to fight!

Sukhaduhkhe same kritwaa laabhaalaabhau jayaajayau;
Tato yuddhaaya yujyaswa naivam paapamavaapsyasi.
38. Having made pleasure and pain, gain and loss, victory and defeat the same, engage thou in battle for the sake of battle; thus thou shalt not incur sin.
COMMENTARY: This is the Yoga of equanimity or the doctrine of poise in action. If a person performs actions with the above mental attitude, he will not reap the fruits of such actions.

Eshaa te’bhihitaa saankhye buddhir yoge twimaam shrinu;
Buddhyaa yukto yayaa paartha karma bandham prahaasyasi.
39. This which has been taught to thee, is wisdom concerning Sankhya. Now listen to wisdom concerning Yoga, endowed with which, O Arjuna, thou shalt cast off the bonds of action!

Nehaabhikramanaasho’sti pratyavaayo na vidyate;
Swalpam apyasya dharmasya traayate mahato bhayaat.
40. In this there is no loss of effort, nor is there any harm (the production of contrary results or transgression). Even a little of this knowledge (even a little practice of this Yoga) protects one from great fear.
COMMENTARY: In Karma Yoga (selfless action) even a little effort brings immediate purification of the heart. Purification of the heart leads to fearlessness.