Miracles enable you to heal the sick and raise the dead because you made sickness and death yourself, and can therefore abolish both. YOU are a miracle, capable of creating in the likeness of your Creator. Everything else is your own nightmare, and does not exist. Only the creations of light are real. Miracles are part of an interlocking chain of forgiveness which, when completed, is the Atonement.
Atonement works all the time and in all the dimensions of time.
Miracles represent freedom from fear. The undoing of fear is an essential part of the Atonement value of miracles. A miracle is a universal blessing from God through me to all my brothers. It is the privilege of the forgiven to forgive. Miracles are a way of earning release from fear.