Charles Ellicott Commentary Romans 10:18

"But I say, Did they not hear? Yea, verily, Their sound went out into all the earth, And their words unto the ends of the world." — Romans 10:18 (ASV)

Have they not heard?—The relations of hearing to belief suggest to the Apostle a possible excuse for the Jews, and he himself puts this excuse forward in the form of a question: “But I ask, did they (the Jews) not hear?” Yes, for the gospel was preached to them, as indeed to all mankind.

Their sound.—Here, this refers to the voice of the preachers; in the original of Psalm 19:4, it is the unspoken testimony of the works of nature, and especially the heavenly bodies, to natural religion (“What though no real voice or sound,” etc.).