The Lord and His apostles demonstrated that they were using the true power of God. To God it is just as easy to cure terminal leprosy as it is to cure a headache. Again and again, the Bible reminds us that the Almighty cannot be limited. Remember the case of Sarah in the Old Testament. She had a severe disability, having been barren all her life. Added to that, “she was past the age” for bearing a child (Hebrews 11:11). Her husband Abraham was so old that he was considered “as good as dead” (Hebrews 11:12). Yet in that obviously impossible situation, God said, “Is anything too hard for the Lord?” (Genesis 18:14). The answer to that question came about a year later when Sarah gave birth to Isaac. The same answer also echoes down through the centuries.
Ah, Lord GOD! It is You who have made the heavens and the earth by Your great power and by Your outstretched arm! Nothing is too hard for You (Jeremiah 32:17).
Your relative Elizabeth in her old age has also conceived a son, and this is the sixth month with her who was called barren. For nothing will be impossible with God (Luke 1:36-37).
Jesus looked at them and said, “With man this is impossible, but with God all things are possible” (Matthew 19:26).
Since real miracles overruled natural processes, it did not matter what the disease was or how impossible it looked. There were no exceptions to what could be successfully healed. Jesus set the standard for miracles of healings, against which all others can be checked for authenticity.
Testing those who claim to heal miraculously is a simple matter of observation. Do they attempt healings that involve physical impossibility? Jesus straightened a withered, deformed hand and made it as fully functional as the other hand (Matthew 12:9-13). Jesus healed an amputated ear, and the person who received healing was attempting to arrest Jesus! (Luke 22:50-51)