Gita Chapter 18.11 to 18.15

Yastu karmaphalatyaagi sa tyaageetyabhidheeyate.
11. Verily, it is not possible for an embodied being to abandon actions entirely; but he who relinquishes the rewards of actions is verily called a man of renunciation.
COMMENTARY: Nature, and your own nature, too, will urge you to do actions. You will have to abandon the idea of agency and the fruits of actions. Then no action will bind you.

Anishtamishtam mishram cha trividham karmanah phalam;
Bhavatyatyaaginaam pretya na tu sannyaasinaam kwachit.
12. The threefold fruit of action—evil, good and mixed—accrues after death to the non-abandoners, but never to the abandoners.

Panchaitaani mahaabaaho kaaranaani nibodha me;
Saankhye kritaante proktaani siddhaye sarvakarmanaam.
13. Learn from Me, O mighty-armed Arjuna, these five causes, as declared in the Sankhya system for the accomplishment of all actions!

Adhishthaanam tathaa kartaa karanam cha prithagvidham;
Vividhaashcha prithakcheshtaa daivam chaivaatra panchamam.
14. The body, the doer, the various senses, the different functions of various sorts, and the presiding Deity, also, the fifth,

Shareeravaangmanobhiryat karma praarabhate narah;
Nyaayyam vaa vipareetam vaa panchaite tasya hetavah.
15. Whatever action a man performs by his body, speech and mind, whether right or the reverse, these five are its causes.

Gita Chapter 7.01 to 7.05

Sri Bhagavaan Uvaacha:
Mayyaasaktamanaah paartha yogam yunjanmadaashrayah;
Asamshayam samagram maam yathaa jnaasyasi tacchrinu.
The Blessed Lord said:
1. O Arjuna, hear how you shall without doubt know Me fully, with the mind intent on Me, practising Yoga and taking refuge in Me!
COMMENTARY: If you sing the glories and attributes of the Lord, you will develop love for Him and then your mind will be ever fixed on Him. Intense love for the Lord is real devotion. With this you must surely get full knowledge of the Self.

Jnaanam te’ham savijnaanam idam vakshyaamyasheshatah;
Yajjnaatwaa neha bhooyo’nyaj jnaatavyamavashishyate.
2. I shall declare to thee in full this knowledge combined with direct realisation, after knowing which nothing more here remains to be known.

Manushyaanaam sahasreshu kashchidyatati siddhaye;
Yatataamapi siddhaanaam kashchinmaam vetti tattwatah.
3. Among thousands of men, one perchance strives for perfection; even among those successful strivers, only one perchance knows Me in essence.

Bhoomiraapo’nalo vaayuh kham mano buddhireva cha;
Ahamkaara iteeyam me bhinnaa prakritirashtadhaa.
4. Earth, water, fire, air, ether, mind, intellect and egoism—thus is My Nature divided eightfold.

Apareyamitastwanyaam prakritim viddhi me paraam;
Jeevabhootaam mahaabaaho yayedam dhaaryate jagat.
5. This is the inferior Prakriti, O mighty-armed (Arjuna)! Know thou as different from it My higher Prakriti (Nature), the very life-element by which this world is upheld.

Asamyataatmanaa yogo dushpraapa iti me matih;
Vashyaatmanaa tu yatataa shakyo’vaaptumupaayatah.
36. I think that Yoga is hard to be attained by one of uncontrolled self, but the self~controlled and striving one attains to it by the (proper) means.

Arjuna Uvaacha:
Ayatih shraddhayopeto yogaacchalitamaanasah;
Apraapya yogasamsiddhim kaam gatim krishna gacchati.
Arjuna said:
37. He who is unable to control himself though he has the faith, and whose mind wanders away from Yoga, what end does he meet, having failed to attain perfection in Yoga, O Krishna?

Kacchinnobhayavibhrashtash cchinnaabhramiva nashyati;
Apratishtho mahaabaaho vimoodho brahmanah pathi.
38. Fallen from both, does he not perish like a rent cloud, supportless, O mighty-armed (Krishna), deluded on the path of Brahman?

Etanme samshayam krishna cchettumarhasyasheshatah;
Twadanyah samshayasyaasya cchettaa na hyupapadyate.
39. This doubt of mine, O Krishna, do Thou completely dispel, because it is not possible for any but Thee to dispel this doubt.

COMMENTARY: There is no better teacher than the Lord Himself as He is omniscient.

Sri Bhagavaan Uvaacha:
Paartha naiveha naamutra vinaashas tasya vidyate;
Nahi kalyaanakrit kashchid durgatim taata gacchati.
The Blessed Lord said:
40. O Arjuna, neither in this world, nor in the next world is there destruction for him; none, verily, who does good, O My son, ever comes to grief!