ought. This is a strong verb, meaning “have an obligation.”

as it is written. This phrase is from Psalm 69:9, the same verse which the disciples applied to Christ when He purged the temple of the money-changers (John 2:17). He suffered reproach on our behalf; we should be willing to be reproached for His sake (1 Peter 4:14).

written for our learning. The Old Testament Scriptures were all written for our benefit today, as well as for the pre-Christian Israelites. Paul very frequently quotes from the Old Testament as authoritative (as in the preceding verse, for example), and clearly believed all of it to be divinely inspired and in every way profitable for Christians (2 Timothy 3:16-17). By no means should Christians limit their Bible study to the New Testament.

God of patience. Note the beautiful titles applied to God in this chapter: (1) “the God of patience and consolation” (Romans 15:5); (2) “the God of hope” (Romans 15:13); and (3) “the God of peace” (Romans 15:33).

as it is written. Again observe how often Paul quotes from the Old Testament, even from what often seem to be obscure verses. This quote is from Psalm 18:49.

again he saith. This quote is from the song of Moses, as he prepared to die (Deuteronomy 32:43). He had led Israel to its promised land, and now, in the final verse of his great song, he exhorted all the nations to rejoice with God's chosen nation, for in Abraham's seed would all nations be blessed. Note also that Paul quotes this exhortation as coming directly from God, even though it was Moses' song, thus confirming the divine inspiration of Moses' writings near the very end of the Pentateuch.

And again. In four straight verses, Paul quotes four Scriptures, from David, Moses, an unknown psalmist, and Isaiah, respectively. This particular quote is from Psalm 117:1. The 117th psalm is the shortest chapter in the Bible, yet one of its two verses is cited by Paul in his letter to Rome.

again, Esaias saith. This reference is taken from the great Messianic promise of Isaiah 11:10, when Christ (“the root of Jesse,” the father of Israel's greatest king, David—hence both “the root and the offspring of David,” as in His claim in Revelation 22:16) will reign over all nations, both Israel and the Gentiles.

God of hope. There are many beautiful appellations given to our God in the New Testament. See note on Hebrews 13:20.

it is written. From Isaiah 52:15, this verse introduces Isaiah's great fifty-third chapter, containing the most complete and poignant exposition in the Bible of the sacrificial death of Christ. Paul, it must be remembered, was writing for the instruction of both the Jewish Christians and the Gentile Christians at Rome, understanding that both would be reading his letter.

Macedonia and Achaia. Paul is referring here especially to the churches of Philippi and Corinth, respectively. Note Philippians 4:15; 1 Corinthians 16:1-3; 2 Corinthians 9:1-4.

by you into Spain. Paul had intended, after taking the offering collected from the various churches of Greece and Asia back to the needy Christians at Jerusalem, to make his next missionary journey a journey to Rome and then to Spain (Romans 15:24). He did not know he would reach Rome only as a prisoner (Acts 28:16) and, as far as the record goes, at least, never get to Spain at all. Nevertheless, his inspired epistles have actually reached every nation, and almost every tribe, on earth.

Amen. Paul normally ended each of his epistles with some such benediction as this. He perhaps intended Romans 16 simply to be something of a postscript. Nevertheless, there is much of great (and inspired) value in that final chapter as well.