Why sayest thou, Jacob, and speakest, O Israel, My way is hid from Jehovah, and my right is passed away from my God?
References for Isaiah 40:27
Dost thou not know, hast thou not heard, that the everlasting God, Jehovah, the Creator of the ends of the earth, fainteth not nor tireth? There is no searching of his understanding.
He giveth power to the faint; and to him that hath no might he increaseth strength.
Even the youths shall faint and shall tire, and the young men shall stumble and fall;
References for Isaiah 40:30
but they that wait upon Jehovah shall renew [their] strength: they shall mount up with wings as eagles; they shall run, and not tire; they shall walk, and not faint.
References for Isaiah 40:31