How he ran then towards Treaty of Passau (1552), towards Siege of Metz and other sad conclusions, "Abdication" the finale of them: these also are known phases in the Reformation History, as hinted at above.
Here at Halle, in the year 1547, the great Kaiser, with Protestantism manacled at his feet, and many things going prosperous, was at his culminating point.

He published his INTERIM (1548, What you troublesome Protestants are to do, in the mean time, while the Council of Trent is sitting, and till it and I decide for you); and in short, drove and reined-in the Reich with a high hand and a sharp whip, for the time being.

Troublesome Protestants mostly rejected the Interim; Moritz and Alcibiades, with France in the rear of them, took to arms in that way; took to ransoming fat Bishoprics ("_Verbum Diaboli Manet_," we know where!);--took to chasing Kaisers into the mountains;--and times came soon round again.

In all these latter broils Kurfurst Joachim II., deeply interested, as we may fancy, strove to keep quiet; and to prevail, by weight of influence and wise counsel, rather than by fighting with his Kaiser.
One sad little anecdote I recollect of Joachim: an Accident, which happened in those Passau-Interim days, a year or two after that drawing of the sword on Alba.

Kurfurst Joachim unfortunately once fell through a staircase, in that time; being, as I guess, a heavy man.