"Calls for liturgical reform
written from a Rationalist perspective began to appear in the 1780s. They
called for drastic modifications to the traditional liturgy or even wholesale
abandonment of it. … Johann Wilhelm Rau argued in 1786 that the old formulas
were no longer usable because the expressions in them were in part no longer understandable
and in part objectionable. Fixed forms in general were not good, and even the
Lord’s Prayer was meant only as an example to follow and not as a prayer to be repeated.
Some said that liturgical formulas served to ease the task of the pastor and
preserve order in the service.

But [according to Rau] the
advantages were specious: very few pastors had so little time left over from
other duties that they could not prepare a service… Each pastor used his own
self-written order or spoke extemporaneously. According to Rau, the most
important abuses to curb were the too-frequent use of the Lord’s Prayer, the
making of the sign of the cross, the Aaronic benediction, chanting by the
pastor, the use of candles on the altar, private confession, the use of the
appointed lectionary texts for sermons, and various superstitious practices
surrounding communion, such as carrying the houseling cloth to catch
crumbs that might fall and referring to the "true" body and blood of
Christ. …

Peter Burdorf, writing in 1795,
argued that repetition in the liturgy weakened the attention of the listener
and the impact of the form. The current liturgy did not hold people’s
attention, nor did the sermon. … Some liturgy was necessary for public services
to be held, but it should be as simple as possible in order to meet the needs
of contemporary Christians. Rationalist writers backed up their words with deeds
and produced a number of new liturgies written with the above concerns in mind.
Luther Reed…offered the opinion that these liturgies "ranged in character
from empty sentimentality to moralizing soliloquy and verbosity." …

Hymns were rewritten as well
with a view to removing "superstition" and outdated theology. . . . This,
then, was the situation around the turn of the nineteenth century. In 1817, the
three hundredth anniversary of the Lutheran Reformation, Claus Harms published
his anti-Rationalistic Ninety-Five Theses, which marked the beginning of a
revival of Lutheran theology and liturgy that was to continue for more than a century.

(Worship Wars in Early
Lutheranism [New York: Oxford University Press, 2004], pp. 127-29)