Having big muscles does not necessarily reflect how strong a person is. If strength is based on physical appearance alone, David would not have defeated Goliath (1 Samuel 17:42)
Everyone has something or someone that they depend on as their strength. However, the greatest strengths comes from above. (Psalm 121:1-2)
The strength that come from the Lord is absolutely reliable: not only is it supreme, it is always constant. (Hebrews 13:8) and comprehensive (Philippians 4:13)
“Do not be satisfied with your natural strength alone because it is very limited. Like David, look up to God for strength to overcome all of life's challenges and do the impossible. Our God is faithful, and can be relied on.”
Memorise: The Lord will give strength unto his people; the Lord will bless his people with peace. (Psalm 29:11) 
