Bhagavad Gita is one such book that provides answers to all your questions; it did for me. I can provide some examples for this statement. You may ask me how could I relate BG with today's world that's full of worries and confusions. Even Arjuna was confused at the beginning of Kurushetra war and Lord Krishna enlightened him and that's how Bhagavadgita was born.
Even before health practitioners and fitness followers emphasize the importance of yoga, the Gita had put it forward hundreds and thousands of years ago. It went a step further and disclosed the importance of not just yoga in its physical form but also the other forms -
1) Jnana Yoga
2) Karma Yoga
3) Bhakthi Yoga
Gita doesn't stop here! It offers the solution to get rid of the pain and pleasures in life by having the right attitude to treat both the impostors the same. It also motivates us to remain detached from the fruits of our work. Ultimately, it guides individuals towards their spiritual journey and helps them attain the ultimate truth.
Regardless of now or 5000 years ago, Bhagavadgita is for every age (or yuga) and it is apt for today's Kaliyuga too. We are living in a misery-ridden world where we fight our own battles every day. By reading Gita, one can understand that the battles are nothing but a delusion about the satisfaction of our ego.
We can relate ourselves to Pandavas & Kauravas and our battles to the battle of Kurukshetra. We do multiple roles at times. We are the noble Arjuna sometimes; when we feel dejected and need that little push from someone like Krishna to know our potential. We are one among the Kauravas sometimes; when we don't know the difference between right and wrong and act according to our ego.
No business school can teach you the essence of management superior to Gita. It teaches a lot of life lessons such as - The importance of decision-making, the difference between knowledge and wisdom, the act of renunciation and selfless devotion. These lessons are in dire need for the spiritual sickness in our present society.
Moreover, in this modern world, we need to understand that the struggle or battle for us is not on the battlefield but it is in us. It's not about victory or defeat but understanding one's own "Self" in the whole process.
Ponder no more and start reading the original Bhagavadgita to find answers to your questions in this Kali-yuga.
Published by Nightingale