You will even expect to SIN, and when you expect to sin you will usually find a way to sin. Smiting the rock twice kept Moses out of the promised land. Giants and well-walled cities do not exist in heaven. Christ is the Rock. He only had to be smitten ONCE for our transgressions.
Death is the penalty for sin.
The soul that sinneth it shall die. And ONE judgment had to be made. Jesus took our judgment. And I, if I be lifted up from the earth, will draw all men unto me. This he said, signifying what death he should die.