The old doctrine of the Church of Scotland in regard to psalmody is tersely expressed in the first book of discipline. "There be two sorts of policie," it is said in that book; "the one of these sorts is utterlie necessary, as, that the word be preached, the sacraments ministered, and common prayers publicly made. The other sort of policy is profitable, but not necessarie, as, that psalms should be sung and certain places of Scripture read when there is no sermon." And in accordance with this doctrine there is very little singing of psalms prescribed as part of public worship in either Knox's Liturgy or the Westminster Directory. In each of these manuals of worship there are only two psalms appointed or supposed to be sung during the minister's service--one before the sermon and another before the benediction. It is possible, however, that there was, from an early period, a third psalm sung in the church by the congregation, although that psalm was not included in the service. Just as in modern churches where instrumental music has been introduced, there is a voluntary played on the organ during the time that the congregation are assembling, so in very ancient times, long before the Reformation, it was customary over a large part of Christendom for the people "to entertain the time with singing of psalms" till the congregation had gathered. And in Scotland within quite recent times the epithet of the "gathering psalm" was commonly applied to what is now called the first psalm. Pasdoran states that, "It was the ancient practice of the Church of Scotland, as it is yet of some Reformed Churches abroad, for the minister or precentor to read over as much of the psalm in metre as was intended to be sung at once, and then the harmony and melody followed without interruption, and people did either learn to read or got most of the psalms by heart." What is here called the ancient practice of the Church of Scotland in the rendering of praise is just the practice that is observed at the present day. But soon after 1645 a different practice arose and continued long in the church. The Westminster Directory for Public Worship recommends that, "for the present, where many in the congregation cannot read, it is convenient that the minister or some other fit person appointed by him and the other ruling elders, do read the psalm line by line before the singing thereof." The practice was accordingly introduced into the Church of Scotland soon after of giving out the psalms in instalments of one line at a time, and so popular did the practice become, and so essential a part of revered use and wont, that very great difficulty was found long afterwards in getting it discontinued. Indeed, the practice of reading the line was pretty general until the beginning of this century.