• You are entitled to the action, never to its fruits
• World & we all are made up of three qualities - sattva(goodness), rajas(passion) & tamas(ignorance) 
• Karma comes from word dharma(duty of each individual) -karma has its cause & effect
• There comes a peace in which sorrows end. 

Bhagwad geeta is a self - actualization book, teaches us to stay detached from moh & helps live us grounded. Also teaches how mindfulness is so so important.

Frankly speaking I to have read this book took me two years I read two pages daily.. Now I'm on the verse of finishing it.  ... I too have got such soul awakening stuff in it.. It is not a hindu book.. It is a self help book on how to live life.. It is for sure a best life book. 

Would recommend everyone to read it & also this article summary by tanmeet kapoor

https://buddingpsychologists.org/messages-from-bhagvat-gita/