And how shall they preach, except they be sent? as it is written, How beautiful are the feet of them that preach the gospel of peace, and bring glad tidings of good things!

People's New Testament

10:15 And how shall they preach, except they be sent? Those must go out to them who have knowledge of the gospel. Hence it was needful that the apostles and evangelists be sent. Hence Christ said, Go into all the world and preach to every creature (Mr 16:15 Mt 28:19). Thus Paul shows the duty was laid upon him to preach to Greek as well as Jew.

As it is written. See Isa 52:7.

How beautiful are the feet of them that preach the gospel, etc. This message was to the Gentiles blessed tidings, and the passage quoted from Isaiah shows, under a figure, how those would rejoice who believed the glad news. See Ac 13:38.

Wesley's Notes

10:15 But how shall they preach, unless they be sent - Thus by a chain of reasoning, from God's will that the gentiles also should call upon him, St. Paul infers that the apostles were sent by God to preach to the gentiles also. The feet - Their very footsteps; their coming. Isa 52:7.

Jamieson-Fausset-Brown Bible Commentary

15. as it is written-(Isa 52:7).

How beautiful are the feet of them that preach the gospel of peace, &c.-The whole chapter of Isaiah from which this is taken, and the three that follow, are so richly Messianic, that there can be no doubt "the glad tidings" there spoken of announce a more glorious release than of Judah from the Babylonish captivity, and the very feet of its preachers are called "beautiful" for the sake of their message.

Matthew Henry's Concise Commentary

10:12-17 There is not one God to the Jews, more kind, and another to the Gentiles, who is less kind; the Lord is a Father to all men. The promise is the same to all, who call on the name of the Lord Jesus as the Son of God, as God manifest in the flesh. All believers thus call upon the Lord Jesus, and none else will do so humbly or sincerely. But how should any call on the Lord Jesus, the Divine Saviour, who had not heard of him? And what is the life of a Christian but a life of prayer? It shows that we feel our dependence on him, and are ready to give up ourselves to him, and have a believing expectation of our all from him. It was necessary that the gospel should be preached to the Gentiles. Somebody must show them what they are to believe. How welcome the gospel ought to be to those to whom it was preached! The gospel is given, not only to be known and believed, but to be obeyed. It is not a system of notions, but a rule of practice. The beginning, progress, and strength of faith is by hearing. But it is only hearing the word, as the word of God that will strengthen faith.