That is not a main point of this essay, however. It appears to be an example of American fundamentalism applied on top of a set of 16th-century Reformation practices. The Bible is held in high regard, which is fine, but it is interpreted through cultural biases and attitudes of several centuries ago. As noted above in footnote 1, the hymnody also avoids 20th century language, ideas, and styles. This too affects the members' theological attitudes, preserving a fundamentalist bias.
People learn to sing what they believe, and learn to believe what they sing.
On the evidence of these materials, faithful Christians are apparently to live as if we are not yet in the 20th or 21st century, but the 16th to 19th. Emphasis is on separatism and distinctiveness from the world, to avoid its evil influences. But I personally believe that Christians should live in the present, engaging it rather than avoiding it . It is possible to be a Christian and a Mennonite without a plain lifestyle or a fundamentalist view. However, the present essay about music is not the place to debate conservative fundamentalism among Mennonites.