God selected . . . what the world calls weak to put the strong to shame. And God also selected (deliberately chose) what in the world is lowborn and insignificant and branded and treated with contempt, even the things that are nothing, that He might depose and bring to nothing the things that are, so that no mortal man should [have pretense for glorying and] boast in the presence of God. —1 Corinthians 1:27-29
If you are weak in faith, in mind, in body, in discipline, in self-control, or in determination, simply wait on God. He will be strong through your weakness.
Isaiah 40:31 teaches that if you expect God, look for Him, and hope in Him, you will change and renew your strength and power; you will run, and not faint or become tired. The Bible doesn’t say “hope so, it could be, or it may be”; it declares that you will be renewed.