Jamieson, Fausset & Brown

But why, &c.--The original is more lively:--"But thou (the weaker believer), why judgest thou thy brother? And thou again (the stronger), why despisest thou thy brother?" for we shall all--the strong and the weak together. stand before the judgment-seat of Christ--All the most ancient and best manuscripts read here, "the judgment-seat of God." The present reading doubtless crept in from Co2 5:10, where "the judgment-seat of Christ" occurs. But here "the judgment-seat of God" seems to have been used, with reference to the quotation and the inference in Rom 14:11-12.