Did Peter teach that?
I quoted ‘By whose stripes you were healed’ (1 Peter 2:24b KJV) as we prayed over Pam, who had suffered for years with a spinal disc despite repeated treatment. It went back in permanently with a loud click – my first experience of many healings of bad backs, such as chronic lateral scoliosis. I soon got quite carried away, and was shocked when another friend told me her back was not healed a week after ministry! I realised I had committed the cardinal heresy of turning an experience into a formula, and a formula into a doctrine! Actually, Peter was not referring there to physical ailments, even though the Holy Spirit made the text relevant to Pam on that specific occasion; Peter had sin in mind:
‘He himself bore our sins in his body on the tree, that we might die to sin and live to righteousness. By his wounds we have been healed’ (1 Peter 2:24).
 Did Isaiah teach it?
Peter of course was paraphrasing the words of Isaiah:
‘Surely he has borne our griefs and carried our sorrows;
yet we esteemed him stricken, smitten by God, and afflicted.
But he was wounded for our transgressions; he was crushed for our iniquities;
upon him was the chastisement that brought us peace,
and with his stripes we are healed’ (Isaiah 53:4-5).
The horrendous sufferings [see the seven emphasised words] were his as he ‘carried’ the griefs and sorrows that are our transgressions and iniquities. ‘Stricken’, the first of those words, is used nearly 60 times in Leviticus 13:0; and 14:0; for the ‘plague’ of leprosy, the metaphor used by Isaiah in his opening chapter for the moral and spiritual condition of Israel in his day (see Isaiah 1:5-6 – sick, bruises, sores, wounds etc).
 Did Matthew imply it?
Matthew also quotes from Isaiah 53:0 in telling of an occasion when
Jesus ‘healed all who were sick. This was to fulfil what was spoken by the prophet Isaiah: “He took our illnesses and bore our diseases”’ (Matthew 8:16-17).
However, Jesus had not yet been to the cross! Matthew is pointing out here that Jesus actually felt the pain of those to whom he ministered; he bore their condition. As Isaiah put it: he was ‘acquainted with grief’ (Isaiah 53:3, literally ‘knowing’; hence ‘by his knowledge’ he is able to ‘justify many’, verse Isaiah 53:11- from their sins). In fact, Peter taught: ‘He bore up our sins [throughout his ministry, right on] to the tree’ (1 Peter 2:24 literal).
 Is healing ‘in the atonement’?
John Stott in his excellent book ‘The Cross of Christ’ dismisses the question in half a page; atonement is for sin, not for sickness. Of course; so let’s reword the question: Is there physical healing through Christ’s death on the cross? The answer is yes. But … our final permanent healing will be a resurrection body when Jesus returns. Temporary healings in our mortal bodies are but foretastes ‘of the age to come’; we need discernment in ministry, because they are ‘distributed according to his will’ (see Hebrews 2:4; 6:4f).