This is a distortion—the passage calls us to labor because God is working in us and with us; thus, the whole process of persevering is a synergistic action, not a monergistic one. I am called to work, and God is working as well. In the final analysis, whether my labor becomes fruitful depends on the donum perseverantiae, that is, on the gift of perseverance on God’s part to preserve me to the end.
