We often misplace and/or miss assign the cause of such. It is always the devil that is the root of anything that isn't love, joy, peace patience, etc., the realm and qualities of our Lord.
It is the adversary who only comes to steal, kill and destroy, steal health, steal wholeness, etc.
It maybe a poison concoction that puts the chink in the armor, it is the devil who attacks the chink in the armor.
Jesus healed them all, they were familiar with the priests healing, Jesus even commanded the Spirits.