Recent research in India discovered that singing Scripture songs is a prominent way believers there spread the Bible. It is a natural, low-cost, and effective way to make the Bible known. Better, it attracts non believers.
New translations of the Bible happen predominantly in places with low literacy rates. Research done in such places showed that almost 25% of Christians who could read learned by signing out of a hymnbook or book of praise songs. Think about it. The person looks at the same words and sings them over and over, week in and week out.
Some learn to read by the sheer force of repeated exposure without being taught. I have written about this before.
Almost everywhere I have been in Africa, believers who see someone translating the Bible into their language ask that their hymns and Scripture songs also be translated and/or published. Unfortunately, this request is too often ignored. That is sad. Perhaps Western missionaries no longer value hymn books because they have largely disappeared from our churches. But we need to make our decisions based on what works in here, not what is useful at home.
Recently, I helped a church in northern Ghana design a program to spread the Gospel in the two largest, unreached people groups of Ghana, together representing almost 2 million people. One of the key elements was the creation and publication of church songbooks in those two languages, so that the church services could be entirely in those languages. Without that, people in those language groups think that Christianity is not for them, but only those who speak other languages.