Working through Claus Westermann’s Praise and Lament in the Psalms, the first part of which was available in English translation in 1965. I wonder if the conclusions Gerald Wilson drew re Ps 89 and Book IV of the Psalter (in his 1981 dissertation, published in 1985) would’ve been different if he’d reflected on the following paragraph:
In Second Isaiah the exclamation has primarily a historical-eschatological significance and not primarily a cultic one. The so-called enthronement psalms are evidence that the message proclaimed by Second Isaiah, that Yahweh had become king, was carried on despite the contemporary situation which showed the opposite. This prophetic assurance lived on in the songs of the postexilic community as one of the witnesses in the waiting for something to come.