A teacher I greatly respect wrote the following. “The word translated “healed” can mean either spiritual or physical healing. However, the contexts of Isaiah 53 and 1 Peter 2 make it clear that it is speaking of spiritual healing. “He himself bore our sins in his body on the tree, so that we might die to sins and live for righteousness; by his wounds you have been healed” (1 Peter 2:24). The verse is talking about sin and righteousness, not sickness and disease. Therefore, being “healed” in both these verses is speaking of being forgiven and saved, not physically healed.”
The problem here is the person didn’t tell the whole story. Although Peter quoted Isaiah 53 in referring to spiritual healing from sin, Isaiah 53:4-5 covers both physical and spiritual healing. In verse 4 the word translated griefs means sickness and disease, the one translated sorrows also means pain. Then in verse 5, we have transgressions and iniquities, which refer to sins.
The Hebrew word translated healed in verse 5 is rapha and always means either a physical healing or a healer. One of God’s names is Jehovah Rapha, the God who heals you. It comes from Exodus 15:26 where the context is the physical diseases of the Egyptians. Therefore both physical and spiritual healing are promised in Isaiah 53:4-5.