When you are depressed, sad & are in distress; in all such times, where from you find your inner strength so as to come out of all such negative symptoms? Is there any God on whom you can rely in all such times? If yes, then where is that God & how can He help you in all such troubled times?
Inner Strength is your Soul strength, Mental strength or Personal Strength which comes into action in your hard times to defeat all such negative symptoms of sadness, depression etc. in your life. In hard times it helps in building your low esteem and loss of confidence. When you are passing through bad times, you have a feeling of self dejection & a feeling that you will not succeed in life. In all such times, your Inner Strength comes into play.
Inner Strength is basically an exploration to find our authentic self. Now how we can peep into & explore our original inner self? Here is a great book "Bhagwat Gita" which is a reservoir of all such questions. "Bhagwat Gita", time & again tells us that we have a Soul inside our human body & this Soul has infinite potential. As this Soul of ours is a spark of the Infinite all powerful, all pervasive Universal Soul, so it's powers are also limit less. This Soul present inside our human body, in fact gives strength to our mind to carry out all difficult tasks. Believing in oneself is nothing but believing in one's inner Soul. All fountains of knowledge & strength come out of this inner Soul only.
"jyotisam api taj jyotis
jnanam jneyam jnana-gamyam
hridi sarvasya visthitam" (Bhagwat Gita: Chapter Thirteen verse 18)
"Sri Krishna said: O Arjuna, He is the source of light in all luminous objects. He is beyond the darkness of matter and is un-manifested. He is knowledge, He is the object of knowledge, and He is the goal of knowledge. He is situated in everyone’s heart."
In Bhagwat Gita: Chapter Thirteen verse 18, God himself tells that He is situated in everyone’s heart & gives strength knowledge & guidance to every human being. So if we have faith in God, faith in our inner Soul then we shall get all the power & Inner Strength to get out of all our adversities.
So let's look inside ourselves so that we can come in touch with our real self (Soul) from where emerges all our Inner Strength. Be yourself & be proud of yourself, as your original self is part & parcel of the Universal Self (God) & with His grace you shall come out of all the adverse circumstances. So have devotion in God & it shall strengthen your mind to face all the challenges of Life.