Albert Barnes on Romans 15:17

Glory. Of boasting, (καυχησιν the word usually rendered boasting,) Jas 4:16, Rom 3:27, 2Cor 7:14, 8:24, 9:3,4, 10:15, 11:10,17. It means also praise, thanksgiving, and joy, 1Cor 15:31, 2Cor 1:12, 7:4, 8:24, 1Thes 2:19 This is its meaning here, that the apostle had great cause of rejoicing or praise that he had been so highly honoured in the appointment to this office, and in his success in it.

Through Jesus Christ. By the assistance of Jesus Christ; ascribing his success among the Gentiles to the aid which Jesus Christ had rendered him.

In those things which pertain to God. Comp. Heb 5:1. The things of religion; the things which God has commanded, and which pertain to his honour and glory. They were not things which pertained to Paul, but to God; not wrought by Paul, but by Jesus Christ; yet he might rejoice that he had been the means of diffusing so far those blessings. The success of a minister is not for his own praises, but for the honour of God; not by his skill or power, but by the aid of Jesus Christ; yet he may rejoice that through him such blessings are conferred on men.

(x) "glory through Jesus Christ" 2Cor 12:1 (y) "which pertain to God" Heb 5:1