Martin Luther on Psalms 122:7

Verse. 7. Peace be within thy walls and prosperitie within thy pallaces.

Nowe that the Prophet hath exhorted all men to pray for the peace and prosperitie of Ierusalem, he turneth vnto the citie, and doth not onely wish wel vnto it, but also he sheweth vnto other how they should pray for it. The summe whereof is that true religion may flourish: the ministerie and ministers of the word may be defended against the false prophets, that concord may be maintained emongst the pastors and preachers of the word, and that the ciuil gouernment may prosper. Howe necessary this prayer is, experience daily teacheth vs. For where these 2. things are, namely concord in the Church, and peace in the ciuill state, there can no good thing be lacking, & therfore the deuil so busily laboureth to trouble the peace of them both. This was the cause why there was such a multitude of false prophets, rebells, & seditious persons emongst this people, as ye stories do testify. Wherfore Dauid being taught by his owne experience, prayeth for these 2. thinges: without the which the world is nothing els but a wild desert.

Example hereof may be vnto vs ye late times wherein we liued vnder the Pope before this light of the Gospel beganne to shyne. For then, when the sound doctrine of the word was lacking, what could the Pope & all his shauelings doe? What one verse did they rightly vnderstand throughout the whole psalter? Wherby it came to passe that they were not able to resist most manifest impieties, which by the strong & mighty delusions of the deuil ouerflowed ye world, as in pilgrimages, where they maintained most damnable idolatries and caused the people to adore the works of their owne handes, and if any man spake against them, he was vp and by taken and burnt as an heretike. So true is it, that when the word is once lost, the world remaineth in most horrible darkenes and can doe nothing else but abuse the giftes of God, and so falleth to most detestable impietie or else to desperation. This Dauid foreseeth, and therefore he prayeth so earnestly for the prosperitie of Ierusalem, for faithfull pastors in the Church, and godly Princes in the politike state.