Albert Barnes on Romans 3:23

For all have sinned. This was the point which he had fully established in the discussion in these chapters.

And come short. Greek, Are deficient in regard to; are wanting, etc. Here it means, that they had failed to obtain, or were destitute of.

The glory of God. The praise or approbation of God. They had sought to be justified, or approved, by God; but all had failed. Their works of the law had not secured his approbation; and they were therefore under condemnation. The word glory--δοξα--is often used in the sense of praise, or approbation. Jn 5:41,44; Jn 7:18; 8:50,54, 12:43.

(b) "all have sinned" Eccl 7:20