Jesus took our diseases and carried our pain (Is 53:4) when we died with him on the cross (Rom 6:5,8). When we were raised with him (Rom 6:4), our diseases were not raised. They are still dead. However, the parts of our bodies that were sick were raised restored with Jesus without any sickness.
So when one a Christian follows Jesus example (Mark 5:23) and commands a sick person to be healed, the are commanding them to be on earth, as they are in Jesus in heaven.