The Hebrew word raphaʾ — to heal, to mend — appears throughout the Psalms and prophets in both physical and spiritual contexts. Psalm 103:3 says God "healeth all thy diseases" — but the context is the full sweep of God's dealings with his people, including forgiveness, redemption, and renewal. The promise of healing is real in Scripture, and so is the pattern of people who did not receive it in the form they asked. Paul's thorn, Trophimus left sick at Miletus (2 Tim 4:20), Timothy's ongoing stomach ailment — Scripture records people of deep faith who carried physical conditions.
Isaiah 40:31 is most often quoted in full, but the full verse has a progression worth noting: "they shall mount up with wings as eagles; they shall run, and not be weary; and they shall walk, and not faint." The order is not escalating triumph — it descends. Flying, running, and then walking. Walking without fainting is placed last, as if it is the most sustained and in some ways most significant of the three. The person who manages consistent, faithful walking with a painful limitation is doing something this verse specifically honors.
Commentary is from a charismatic Protestant perspective, drawing on KJV text and public-domain sources including Spurgeon, Andrew Murray, and Matthew Henry.