The arm of flesh refers to efforts that are solely based on the wisdom, ability and strength of man. Unfortunately, the best of such efforts is limited in any venture, because the spiritual controls the physical.
Similar to the scenario that played out between hezekiah and sennacherib. Although the almighty is a great Ally to have, he is also a dangerous enemy to engage in battle. Everyone who lives in sin is at war with him.
Are you one of those who have not decided to be a friend of God? You must have a rethink today and stop trusting in man or in your strength instead you should trust in God.
Jesus is Lord, mighty in battle, and he will fight for you if you will let him be lord indeed over your life from today.
If you have been putting your trust in the arm of flesh, perhaps in the form of secret societies you belong to or black magic charms in your possession renounce today and surrender to Jesus.