Martin Luther in his Commentary on Galatians:
The monks imagined the world was crucified unto them when they entered the monastery. Not the world, but Christ, is crucified in the monasteries.
To trust in our religious devotion for justification is to be ever-striving, because we are ever-sinning. This theoretical recycling of salvation assumes Christ's original work did not justify us "once for all" but must continue to be accessed through our efforts, treating justification like a spiritual game of Whack-a-Mole.
To taste of the heavenly gift and fall away from the gospel of justification by grace through faith is to "crucify once again the Son of God to our own harm" (Heb. 6:6).