Faith is like physical fitness. Physical fitness from regular stretching, walking or running doesn’t last unless we keep exercising. Neither faith nor fitness is of benefit as a once off, or once practised discipline. Hebrews 3:12-15 reminds us that while Jesus’ sacrifice was a once-off act of rescue, our response to it must be continual. We must help each other to hold tight to our faith, exercising and growing it daily.