'Strength' in the Bible

and thou shalt love the Lord thy God with thy whole heart, thy whole soul, thy whole mind, and thy whole strength.'

and To love Him with all one's heart, with all one's understanding, and with all one's strength, and to love one's fellow man no less than oneself, is far better than all our whole burnt-offerings and sacrifices."

Then He came and found them asleep, and He said to Peter, "Simon, are you asleep? Had you not strength to keep awake a single hour?