A strong body needs good food and exercise.  Food fuels the body and exercise makes it stronger.  If we don’t eat healthy food and exercise our body will eventually become weak and inflexible and even the smallest physical exertion will cause injury to our puny muscles.

Our physical life mirrors our spiritual life.  If we are not consuming the right spiritual food (Word of God) we will soon become weak and inflexible and the smallest adversity or prosperity will break our puny spiritual muscles.  No matter what our circumstances, good or bad, we will be miserable, stressed and complaining.
If we routinely consume the Word of God, this gives us spiritual energy to handle the trials and pressures of life.  When we apply Biblical truth to our daily circumstances we are ‘spiritually exercising’ which in turn builds spiritual muscle.  Spiritual muscle is a relaxed mental attitude, a strong faith, a Christ-like love and confidence under pressure. (2Cor 4:7-18)
The more we exercise the more spiritual muscle we build.   The greater our spiritual muscle – the greater our capacity to handle pressure, adversity and prosperity.
God designed us to have abundant spiritual strength to handle our own problems and eventually be strong enough to help family, friends and others will their load.
“But those who wait on the Lord shall renew their strength; they shall mount up with wings like eagles, they shall run and not be weary, they shall walk and not faint.” Isaiah 40:31