John Chrysostom

He does not say merely with one mouth, but bids us do it with one will also. See how he has united the whole body into one, and how he concludes his address again with a doxology, whereby he gives the utmost inducement to unanimity and concord.

Homily on Romans 27 ↗

Theophylact of Ohrid

What then is the fruit of like-mindedness? The glorification of God not only with one mouth, but also with one soul (for this is what "with one accord" means). Here the word "God" should be separated, referring it to the preceding phrase, and then read with a new beginning: "and Father of our Lord Jesus Christ." However, there will be no impropriety if these words are read together as well, that is, understanding "God and Father" in relation to One and the Same Christ; for God the Father is the God of Christ according to His …

Commentary on Romans ↗

Thomas Aquinas

That, by the fact that you agree on the same things, with one mind, existing through faith and consensus of charity, as it says in a psalm: who makes men of one mind to dwell in a house (Ps 67:7), i.e., with one confession of the voice coming from unity of faith, 1 Corinthians: I appeal that all of you agree (1 Cor 1:10), that for the conformity of the heart, you may glorify God, Creator of all things, he himself existing as the Father of our Lord Jesus Christ, through whom he adopted us as his sons: those who honor me I will honor …

Commentary on Romans ↗