...but glorified or damned in accordance with our merit.
God either made us free being, or he did not. Merit means, IMHO, our acceptance of God’s grace, and by grace I include all his gifts, natural and supernatural. In a real sense, since their all comes form Him, it is hard to separate one from the other, except notionally. Paul compares himself to an athlete. He “ ran” his race like a championship athlete. Most of us just jog along, and rest content with finishes the course, or maybe even refuse to start, or take off on our own course. He ran to win the prize. God blesses us with what we need. He shows us the way, he has reached the goal before us, and beckons us to follow. There he stands, the master of the waves, and if we falter, we need but reach out our hand and he will save.