It is not that Bhagavad Gita is just a compendium of philosophical thoughts. Just like any other philosopher whose intention is to reach people, Vyaasa uses lots of imagery and beautiful poetic language to explain the concepts. Some of them are given here.

Before going to the similes and metaphors, let us consider this beautiful construct. In Chapter 2 verse 5, Arjuna says that by killing the teachers, the wealth he gets will be tainted with blood. (Hatva artha kaamaastu Gurun nihaiva, bhunjeeya bhogan rudira pratigdhan). Compare this with Macbeth’s lament ‘All the perfumes of Arabia will not remove this stain’ after killing his king. The difference is that Arjuna was able to visualize it before committing the killings.

The most quoted and chanted verse about the soul discarding this body just like a dilapidated cloth and taking on new robes is one of the best similes. ‘Vaasaansi jeernaani yatha vihaaya, navaani grihnaani naroparaani, tatha shareeraani vihaaya jeernaani, anyaani sanyaati navaani dehi’ – verse 22 chapter 2

Another simile much used in philosophy is the tortoise. Krishna says the man with steadfast mind and perfect knowledge reaches that state by withdrawing all the senses like a tortoise ‘Yadaa samharate chaayam koormongoniva sarvashah, indriyaanin indriyaartebhyah tasya pragnaa pratisthitah’ Verse 58 chapter 2

A very beautiful simile is the ocean remaining unperturbed even though all the rivers are pouring water into it. Similarly one who remains unperturbed while approaching all the sense objects achieves peace ‘ aapooryamanam achala pratitham samudram eva api mukhaa dravanti, tadvat kaamaan yam pravashanti sarve sa shaatim aapnoti na kaama kaami’ – verse 70 Chapter 2

While talking about lust which is the root cause of all disturbances of the mind, Krishna gives three beautiful examples of a superior object being covered and masked by an inferior object
1. The fire engulfed by smoke (dhoomenavriyatovahnih)
2. A mirror covered by dust (yata darsho malena cha)
3. An embryo covered by the placenta (yatolpena vrito garbhah)

The beauty of these examples is that they all talk of very superior/useful things like fire, baby or a mirror but covered by very useless objects with a telling effect on the concept which He propounds (Verse 38 chapter 3)

The poet in Vyaasa sometimes comes out very prominently. He combines a simile and a metaphor in just one verse 37 of Chapter 4. He says just like fire turns all the fuel into ashes, the fire of knowledge turns all action into ashes. ‘Yathaidhamsi samitoni bhasma sat kuruteh Arjuna, gnanagnih sarva karmaani bhasmasat kurute tatha’

Another very famous simile is the lotus leaf in water. In verse 10 of Chapter 5, He says ‘Brahmanyaadaaya karmaani sangam tyaktva karoti yah, lipyate na sa paapena, padma patram ivaambhasaa’ meaning ‘He who shakes off all attachment and offers everything to God, him is not touched by the sins of the action just as water does not wet the lotus leaves though they live verily in it’.

One more place where the poet Vyaasa takes recourse to poetic language is in verse 3 of chapter 6. Swami Parthasarathy beautifully interprets this as Krishna’s way of driving home a point to a warrior. Arjuna will understand the language of mounting a horse easily and so He says ‘ Aarurooksho munair yogam karma kaaranam uchyate, yogaaroodhasya tasyaiva, shamah kaaranam uchyate’ meaning ‘To the contemplating soul who desires to ride the heights of karma yoga, disinterested action is called the first stepping stone; for the same man when he is mounted on the horse of yoga absence of all worldly thought is said to be the way to blessedness’

‘Yataa deepo nivaatastho na ingathe sopama smiritah, yogino yata chittasya, yunjato yogam aatmanah’ ‘Just as a lamp does not flicker in a windless environment, so does the mind of the yogi who has fixed his mind on the Yogaatma’ – verse 19 chapter 6. This simile of a lamp is windless environment is again used in many philosophical discussions

Can there be a better and more effective comparison of the uncontrollable mind to the wind in verse 34 of Chapter 6 ‘Vaayoriva sudushkarm’?

In Chapter 7, verse 7, He gives another beautiful simile, 'evrything existing is tied to Me just like beads to a string' - 'mayi sarvam idam protam sootrey mani gana iva'. The beads cannot remain stable if the string is broken and so also every entity in this Universe is kept in its place by Him.

Probably Chapter 8 is a rare chapter where I could not find one simile or metaphor, Krishna (or Vyaasa) must have become too philosophical to indulge in any frivolities.

In chapter 9, verse 9, a grand example of the air being contained within the space illustrates how all created things reside within Him. Yataakaasha sthito nityam vaayuh sarvatrago mahaan, tathaa sarvani bhootani matshaanityupadaarayah

Chapter 10 and 11 are showing Vyaasa at his best in poetry. In a truly literateur's manner, he brings in all the best in the world and tell them to be direct manifestation of Krishna, in Chapter 10. Chapter 11 is a typical Spielberg scene, of grandeur, images of humongous proportions et al.

In chapter 11, there are two very beautiful descriptions of how the beings are flowing into the gory mouth of death, just like a river flowing into the sea and just like moths fly into the flame. Two very beautiful comparisons that will definitely please any one of literary pursuit. Yada nadeenam bahavembu vegaah samudram evaapi mukha dhravanti, tada tavaami nara loka veerah, vishanti vaktraani abhi vijwalanti. Yadaa pradiptam jwalanam patangaah, vishanti naashaaya samruddha vegah, tadaiva naashaaya vishanti lokaas tavaapi naashaaya samruddha vegah.

In Chapter 12, Vyaasa displays a deep penchant for building up a step by step methodology starting from the most complicated, coming down to the easiest and ultimately concluding that the simplest is the most effective. This he has done in other places also but before looking at them, let us see this which is very elaborate. Five verses are involved.

Mayyeva mana aadatsva mayi buddhim niveshayah
Nivasishyasi mayyeva ata oordhvam na samshayah

Atha chittam samaadhaatum na shakroshi mayi sthiram
Abhyaasa yogena tato maam ichhaaptum dhananjaya

Abhyaaset asamarthisi mat karma paramo bhava
Madartham api karmaani kurvan siddhim avapsyasi

Athaitabyasaktoshi kartum adhyogam aashritah
Sarva karma phala tyaagam tatah kuru yataatmavaan

Shreyo hi gnanam abhyaasat gyaanat dhyaanam visishyate
Dhyaanat karma phala tyaagam tyaagat shantir anantaram

Krishna says, ‘Arjuna, concentrate upon me, fix your mind on me and you will reside with me’.
‘If you are unable to fix your mind upon me, try abhyaasa yoga – practice of the science of uniting the individual consciousness with the Ultimate Consciousness by remembering me constantly’.
‘If even that is not possible, dedicate yourself to the duties of me’.
‘Lastly even if that is not possible, don’t worry, do everything with a sense of dispassion and renounce the results unto me’.

These are the step by step techniques. Remember that He is addressing people of various levels of the state of the mind.

And in the concluding para of this discussion, He declares, ‘the knowledge of uniting the individual and Ultimate Consciousness (second technique) is better than the first, third is better than the second but the fourth, karma phala tyaagam, is the best of all’.

Having enjoyed this, let me put down the other places where I enjoyed Krishna’s arguing prowess.

In chapter 2, He discusses the consequences of desire. He says, ‘When you concentrate on wordly things, you develop an attachment, from the attachment, a desire to possess them arises and from the desire arises anger, either to protect it or for not possessing it, anger results in delusion of mind and deluded mind is the cause of all devastation’.

Dhyaayate vishayaan pumsah sangasteshoopajaayate
Sangaat sanjaayate kaamah kaamat krodhobhijaayate

Krodhat bhavati sammohah, sammohaat smriti vibhramah
Smriti vibhramashaat buddhi naashah buddhi naashaat pranashyati

Again in Chapter 3, he analyses how performing one’s duties of in a renounced manner results in rain and welfare of everybody. He declares, ‘Beings survive because of food and food is generated by rain, rain is created by the yagnas, but the yagnas are the result of perfoming one’s karma, these karmas are prescribed by Vedas and Vedas have their origin in the Supreme Being, so devote everything into That Supreme’.

That was a little digression from my main thread of listing out the similes and metaphors. In chapter 13, two more grand pictures are painted. Just as the space is not tainted by the air it contains, the Supreme Being is not tainted by all the beings it contains. And in the next verse, He compares the Sun lighting the universe eternally, the Supreme Being (Kshetragna) gives life to every being.

Tataa sarva gatam sowkshamyat aakaasham na upalipyate
Sarvatraavasthito dehay tathatmaa na upalipyate

Yatha prakaasha yatyekah krtsnam lokam imam ravih
Kshetram kshetree tatha krtsnam prakaashayati tat param

The deepest philosophy comes in chapter 15 Purushotama Yoga when Krishna gives the example of an inverted tree.

The universe (or human body) may be compared to an eternal tree that has its origin (or root) in the Supreme Being and its branches below in the cosmos. The Vedic hymns are the leaves of this tree. One who understands this tree is a knower of the Vedas.

Oordhvam moolam adhah shakham aswattam praahuravyayam
Chhandansi yasya parnaani yastam veda sa veda vit

I would suggest interested readers to take up some guru’s explanation depending on his/her inclination like Sankara, Ramanujam, Swami Chinmayananda, Swami Parthasarathi and read it because I consider myself to be too ignorant to explain this.

A superb illustration of how beings take their vasanas or desires (in the form of the six senses) to the next birth is given by comparing it to the air which takes the smell from the flowers wherever it goes. Verse 8 of chapter 15

Shareeram yad avaapnodi yaccapyutkraamateeshwarah
Gruheetwaitaani sanyaati vaayur gandhaani vaasayat