not move a finger—(also: not lift a finger) not make the slightest effort to do smth.:
- It is unbelievable but my husband will not move a finger to help me on the domestic front.
not move a muscle—
1. remain perfectly motionless:
- Find yourself a comfortable, out-of-sight place to sit, keep quiet, and don’t move a muscle.
2. = not move a finger:
- I can’t believe Christians would let a thing like this happen and not move a muscle to help her.