Semper Reformanda

It was Jodocus van Lodenstein, Dutch Puritan, who first coined the saying Ecclesia semper reformanda est ("the church must always be reforming") (Michael Bush, "Calvin and the Reformanda Sayings," in Herman J. Selderhuis, ed., Calvinus sacrarum literarum interpres: Papers of the International Congress on Calvin Research (2008), p. 286).

Andrew Symington, The Principles of the Second Reformation:

The period commencing in 1638, and continuing for the ten years which follow, has been usually known, in the ecclesiastical history of this country, by the designation of the Second Reformation, to distinguish it from a period of longer duration in the preceding century, usually called from its priority, not its excellence, the First Reformation.

Cotton Mather, Introduction to Magnalia Christi Americana, Vol. 1, p. 26:

'Tis very certain, that the first Reformers never intended that what they did should be the absolute boundary of Reformation, so that it should be a sin to proceed any further; as, by their going beyond Wicklift, and changing and growing in their own Models also, and by the confessions of Cranmer, with the Scripta Anglicana of Bucer, and a thousand other things, was abundantly demonstrated.

James Kerr, A Third Reformation Necessary: or, The Piety, Principles, and Patriotism of Scotland's Covenanted Martyrs; With Application to the Present Times:

In the Reformations in the times of Luther, and Knox, and Henderson, the people awoke from their lethargies and rose up in new life to carry on the work to its completion. Be up then and doing, we beseech you, and, by the help of Almighty God, we may yet succeed in driving the battle to the gate. The restoring of the ruined temple of the Covenanted Reformation, and thereby the effecting of a Third Reformation for Scotland,—this is the work of the present hour, the work of every true patriot, of every lover of the Church, of every lover of Christ’s crowns. "When Christ comes," said Richard Cameron, "to raise up His own work in Scotland, He will not want men enough to do it." May He come soon, then, to raise up His tabernacle that is fallen, and restore it from ruins, as in days of old! Awake! why sleepest Thou? Pluck Thy hand, even Thy right hand, out of Thy bosom. Gird Thy sword upon Thy thigh, Most Mighty, and ride forth for the sake of truth, and meekness, and righteousness. Take to Thee Thy power and reign. Reign over Scotland, and over Ireland, and over England. Reign over Europe, and over Asia, and over Africa, and over America. Take the throne of every heart, and the throne of every household, and the throne of every community, and the throne of every church, and the throne of every nation, and the thrones of all worlds; and let every knee bow and every tongue confess that Christ is Lord, to the glory of God the Father.

"Thou shalt arise, and mercy yet
Thou to Mount Zion shalt extend;
Her time for favour which was set,
Behold! is now come to an end.

"Thy saints take pleasure in her stones;
Her very dust to them is dear;
All heathen lands and kingly thrones
On earth Thy glorious name shall fear."

And, when this sublime prophecy of Old Testament times shall have been fulfilled, there shall go up from the redeemed and emancipated millions of the broad earth, as the voice of many waters, and as the voice of mighty thunderings, the triumphant ascription,—"Alleluia! for the Lord God Omnipotent reigneth!"