Is it God’s will to heal everyone? This question is guaranteed to come up in almost every Christian’s life; our lives have been, or will be, touched by sickness at one time or another, either in our own bodies or in those whom we love. There are many who answer “yes,” but then say that the reason a sick person is not healed is because of a lack of faith, either in him or in the one praying for him. Yet, this answer is not at all obvious in the Bible – in fact, we have good reason to think otherwise (apart from the serious problems with the question itself which I have discussed here).
First, we must recognize that God often claims to be the ultimate cause for sickness in the Bible. In response to Moses’s unwillingness to return to Egypt as His spokesman, God said to him, “Who has made man’s mouth? Who makes him mute, or deaf, or seeing, or blind? Is it not I, the LORD?” (Exodus 4:11). Again, at the end of Deuteronomy God says that He brings both life and death, “See now that I, even I, am he, and there is no god beside me; I kill and I make alive; I wound and I heal; and there is none that can deliver out of my hand.” (Deuteronomy 32:39). After God grant’s Hannah’s request for a child (Samuel), she praises Him, saying, “The LORD kills and brings to life; he brings down to Sheol and raises up.The LORD makes poor and makes rich; he brings low and he exalts.” (1 Samuel 2:6-7).
Lastly, in Isaiah God again makes the bold claim, “I form light and create darkness, I make well-being and create calamity, I am the Lord, who does all these things.” (Isaiah 45:7). Clearly, we can at least say that in some cases God has actively willed sickness so it cannot be His will to heal everyone. We have an explicit example of this in Uzziah (Azariah), King of Judah. Although Uzziah was a good king (2 Chronicles 26:4) he became prideful and entered the temple in order to burn incense on the altar – a duty restricted to the Levitical priests (2 Chronicles 26:16-21). Because of his pride, God struck him with leprosy until the day that he died (2 Kings 15:6, 2 Chronicles 26:19-21).
This is not only true in the Old Testament. In the New Testament, Jesus and the Apostles did not heal everyone they came into contact with. Jesus Himself only healed one man from among the “multitude of invalids” (πλῆθος τῶν ἀσθενούντων) at the pool of Bethesda (John 5:1-9). Likewise, He did not heal people in His hometown of Nazareth because they rejected Him (Matthew 13:58). It cannot be said, however, that Jesus’s healing was dependent on the faith of those whom He chose to heal (although there is a close connection) for the following reasons. First, those whom Jesus raised from the dead could not exercise faith. In the case of the widow of Nain (Luke 7:11-17), Jesus simply had compassion on her and her son – their faith (or lack thereof) is not even mentioned. Second, Jesus healed those who obviously did not have faith. The prime example of this is when He cleansed the 10 lepers in Luke 17:11-19. Only one of the lepers returned to give thanks to Jesus, thereby showing his faith; the other nine did not even have the decency to thank the one who healed them.
Furthermore, there are examples of godly men in both the Old and New Testaments who had (as far as we know) unhealed sicknesses – or at least they were not healed in the miraculous way that many claim is God’s will. Job was a man singled out by God Himself as exemplary, yet he underwent all sorts of afflictions including illness. Elisha became sick with an illness that caused his death (2 Kings 13:14). Paul stopped at Galatia because he was sick (Galatians 4:13-14). Timothy had frequent illnesses (1 Timothy 5:23). Paul had to leave his companion, Trophimus, behind at Miletus on one of his journeys because he was ill (2 Timothy 4:20). These show that godly believers should not expect their lives to be characterized by perfect health. To be sure, God may grant special healing to some of His children, but He is under no obligation and has not promised it to all of us this side of eternity.
Second, the nature of the thorn. While some interpreters have debated the nature of Paul’s “thorn,” the most natural identification of it is a physical ailment. The primary reason for this is that in the following verses, the thorn is identified as a “weakness” (ἀσθενεία, v.9-10) and distinguished from persecution (διογμός, v.10; the most common alternative interpretation). Pauline scholar Douglas Moo points out Paul uses the word “weakness” (ἀσθενεία) elsewhere to refer specifically to physical incapacities (Galatians 4:13, 1 Timothy 5:23).
Third, the result of Paul’s prayers. Having seen that Paul’s thorn was ultimately sent by God, and that it was a physical ailment, the way Paul’s prayers are answered is even more significant. God responds, not by healing Paul, but by saying “My grace is sufficient for you, for my power is made perfect in weakness” (v.9). God’s response to Paul is that in the midst of his suffering – God’s grace is sufficient. It is sufficient to carry Paul through his pain; it is sufficient to provide the strength needed for Paul’s mission. More than that, in relying on God’s grace in his weakness, Paul manifested the perfect power of God. This is why Paul responds by saying, “For the sake of Christ, then, I am content with weaknesses” (v.10). If Paul had been healed, his response would be nonsensical.
In conclusion, we must recognize that sickness and disease are included in the sufferings that a Christian will undergo during their sojourn on this earth. Recognizing this give us the confidence that God will use these things to produce endurance, character, hope (Romans 5:4), and steadfastness (James 1:2-4). They are not random but rather are used for our good (Romans 8:28) and under the perfect control of God (Ephesians 1:11). This does not mean we do not pray, but rather fills our prayer with confidence. For if it were God’s will that everyone should be healed, and everyone is not healed, it must mean that there is something else (Satan, demons, ourselves) capable of frustrating the will of God and preventing Him from healing us. To be sure, God can, and does, chose to heal today, either miraculously or through the use of secondary means. Through it all, whether He chooses to heal us instantly, over a long period of time, or not until the resurrection, we can know that He is sovereign and working for our good and His glory.
 Moo, Douglas. “Divine Healing in the Health and Wealth Gospel.” Trinity Journal, 1988, p. 201.