Summary on the Yoga Sutras of Patanjali

Yoga Sutras describes the way of overcoming the afflictions of the body and fluctuations of the mind: the obstacles to spiritual development. The following summary is based on 5 sutras from each chapter.
Chapter 1: Samadhi Pada-On Contemplation
Verse 1: atha yoganusasanam
Now, seems to be the key word in this verse. You can relate it to “Carpe diem” a Latin term used to describe the phrase seize the day. Live like it is your last day, leave no room for procreation. To act now in the present.
Verse 15: drsta anusravika visaya vitrsnasya vasikarasamjna vairagyam
This verse talks about renunciation and how non-attachment and detachment must be learned by will power. When the five sense of perception and five organs of actions have been silenced self realization is attained. Both abhyasa(path away from pleasure and pain towards bliss) and vairagya(path of detachment) are essential for self-realization. One should be indifferent from all thoughts and emotions and to lead one’s life through their citta (consciousness).
Verse 33:maître karuna mudita upeksanam sukha duhkha punya apunya visayanam bhavanatah cittaprasadanam
Taking verse 15 as a reference, once you are able to plant the seed of joy, detached and indifferent from all thoughts and emotions, this mental adjustment and approach to life keeps the mind of the sadhaka (practitioner) serene and pure. Basically, to lead one’s life with your consciousness forward.
Verse 20: saddha vira smrti samadhiprajna purvakah itaresam
To purse ones practice with faith and strength and to use memory as a guide to leap forward with wisdom, to be in total absorption and awareness. This state is called upaya pratyaya, once you have reached this state one should remember abhyasa and vairagya to break out of spiritual isolation which is not freedom. The practicner should use sraddha (faith with mental and intellectual firmness) to intensify his practice. If trust is instinctive, faith is intuitional. Lead your practice with intuition.
Verse 41: ksinavrtteh abhijatasya iva maneh grahitr grahana grahyesu tatstha tadanjanata samapattih
Patanjali describes Samapatti , the balanced state of mind of the seer (soul) who having attained samadhi, radiates his own pure state. The citta (consciousness) is then like the still, clear water of a calm lake. It transforms itself to the level of the seer (soul), and reflects its purity without refraction. Thus experiencing the true state of the soul.

Chapter 2- Sadhana Pada (On Practice)
 
Verse 3: avidya asmita raga dvesa abhinivesah klesah
To know the 5 afflictions of the brain which disturb the equilibrium of consciousness are;
1) Ignorance(lack of wisdom)
2)ego
3)pride of the ego, sense of I
4) Attachment to pleasure aversion to pain
5) Fear of death (clinging to life)
Afflictions are of 3 levels, intellectual, emotional and instinctive. The sadhaka must learn to locate the sources of the affliction, in order to remove them through his yoga principles and disciplines.
Verse 10: te pratiprasavaheyah sukamah
The 5 afflictions are to be eradicated by the process of involution, to look within yourself and silence the affliction at its very source. The mind’s focus is toward the seer (soul) by the process of pratyahara. Withdrawal of the mind from its contact with the senses of perception and organs of action; then the mind’s direction is towards the soul. In doing so one is ready for meditation.
Verse 12:klesamulah karmasayah drsta adrsta janma vedaniyah
Karma or the universal law of cause and effect applies to past present and future lives. To be free from the wheel of desire and lead one life towards the sate of bliss through the practice of kriyayoga, to try and remove residual karma.
Verse 18: prakasa kriya sthiti silam bhutendriyatmakam bhogapavargartham drsyam
This verse talks about the 3 gunas, sattva (brilliance), rajas (action) , tamas (laziness) that are established in the elements of nature, senses, mind, intelligence and ego, serving the seer (soul) for the purpose of experiencing pleasures or emancipation. The 8 limbs of Yoga will help purify the seer (soul) that is clothed with the 5 sheaths allowing one to experience freedom.
Verse 33: vitarkabadhane pratipaksabhavanam
The principals that prevent yama and niyama are to be counted with right knowledge and awareness. One should learn to balance their thoughts by going deep into the cause o f his anger or violence and to study the opposite force with calmness and patience. Also known as paksabhava
e.g: Adjusting ones Asanas cultivates health on a physical level helping the organic system to function rhythmically at physiological level, which effects changes in the senses, mind and intellect at a mental level. This adjustment and observation in the practice of yoga fuses paksa (one side) and pratipaksa and pratipaksa (both sides) allowing one to free himself. The pose first brings inner balance and harmony, but in the end it is merely the outer expression of the inner harmony. In doing so one is able to meditate and free himself from uncertain knowledge.
Chp 3: Vibhuti Pada (On Properties & Power)
 
Verse 3: tadeva arthamatranirbhasam svarupasunyam iva samadhih
Subject, object, experience. When meditating become the object. For example; reader, book , reading. Become the shake not the shaker. When consciousness appears to have ceased and you have reached a profound state of serenity, Samadhi is reached.
Verse 9: vyutthana nirodha samskaryoh abhibhava pradurbhavau nirodhaksana cittanvayah nirodhaparinamah
The silent moments between thoughts, where there is stillness and silence are to be prolonged into extra-chorological moments of consciousness, without beginning or end. So that, there is room for generation or restraint of thoughts. Consciousness has three dharmic characteristics; to wander, to be restrained and to remain silent. Transform the silence into single state awareness.
Verse 14: santa udita avyapadesya dharma anupati dharma
The moulding of consciousness takes place owing to the change in the gunas of nature. Point zero indicates the point of balance and harmony at which we can unlock and liberate the knotty confusion of matter and emotion. Every moment in the present you are moulding your future. Live life consciously.
Verse 24: maitryadisu balani
Be kind and compassionate to others around you in doing so one gains moral and emotional strength. To regards things impartially without becoming involved.
Verse 48: grahana svarupa asmita anvaya arthavattva samyamat indriyajayah
When the organs of actions become passive and a state of quietness is experienced, the cultured intelligence will turn inwards exploring the realm of the seer so that the mind and ego are brought to rest permanently.
Chp 4: Kaivalya pada (On Emancipation & Freedom)

Verse 2: jatyantara parinamah prakrtyapurat
With consistence practice the practicner afflictions and fluctuations can be brought under control and transformed enabling him to live in a pure dynamic state in this present life.
Verse 7: karma asukla akrsnam yoginah trividham itaresam
This sutra talks about the fourth action one that is free from its fruits and duality. Ambition is transformed into spiritual aspiration. In doing so the practicner becomes refined, mind and consciousness become clear and action cleaned. To act without motive or desire
Verse 14: parinama ekatvat vastutattvam
We see objects according to the predominating gunas in one’s intelligence, an object is perceived differently although its essence remains the same. Truth is one and we must experience it in its real essence. If intelligence and consciousness are filtered and refined, both subject and object retain and reflect their real essence.
Verse 16: na ca ekacitta tantram ced vastu tat apramanakam tada kim syat
When intelligence and consciousness touch the supreme knowledge, one remains merely an uninvolved witness of objects. If an object does not stimulate the mind, it remains unperceived by the mind or the mind fails to grasp it. When the mind is freed from the play of gunas, it sees objects in their true reality, and remains free from impressions. The mind and soul become one, and are one with the essence of all objects.
Verse 21: cittantaradrsye buddhibuddhehatiprasangah smrtisankarah ca
The practice of yoga disciplines and cultures the consciousness of the head, by which it perfects the art of analysis, judges precisely, experiences unalloyed bliss, becomes auspicious and moves towards matures intelligence (consciousness of the heart) and unalloyed wisdom. This return of the consciousness from the seat of the head towards the seat of the spiritual heart is purity of consciousness.