Without trying to, the above article does a nice job of linking Modernist thought, which updates morality to keep pace with “the people of our time” (in contrast with the Catholic belief about morality having certain degrees of certainty) with it’s roots in Lutheranism.
Luther desired to place all his religious trust in the Scriptures. The belief was, “Sola Scriptura”, meaning Scripture Alone, was to be the source of Church authority. Because he didn’t want Germany and all Christendom to become a mad house with multiple versions of Christianity, the secondary authority was the State (mainly the local princes) to enforce this version of Christianity.
Sola Scriptura’s sole trust in the Bible means that Papal and even Church Council authority was undermined. If these sources of authority couldn’t prove their points by Scripture, than they shouldn’t be listened to. This logically proceeds to the idea that every preacher might be ignored if the right contrarian Bible verse is found. Originally this meant teaching authority was based upon scholarly research, so Protestant preachers like John Knox switched from Religious garb to Scholarly garb:
However, another seed was planted by Luther to undermine this Scholarly Authority, and it was his distrust of reason. He once said, “Reason is directly opposed to faith, and one ought to let it be; in believers it should be killed and buried” (Jacques Maritain’s Three Reformers). This is in opposition to the Christian tradition of using reason to enlighten our faith.
Combining both a distrust of reason and a trust only in the Scriptures means any unschooled individual has a just as valid an interpretation of Scripture as any schooled preacher might have. Just the other day I heard Alistair Begg on the radio telling his congregation just that: preachers are simply guys without authority but with knowledge. His point was that preachers can be trusted to have done research but they could be very, very wrong and so there is an obligation to figure it all out on one’s own.
This leads directly to Modernism. The people decide what is right and wrong. Truth is held only in our hearts, and isn’t external to us. To find truth the learned must therefore look to the hearts of the unlearned. As the article says, “the Church needs to conform to the opinions of ‘the people of our time.'”
The logical out growth of Lutheranism’s rejection of various authorities is into Modernism. This connection shows some parts of Modernism are the flowering of ideas at least 500 years old.