The essential parts of worship we are at no loss to discover, clearly indicated as they are in the history of the Apostolic Church. Praise and Prayer, with the reading and exposition of Scripture, together with the celebration of the Sacraments, are repeatedly referred to as those exercises in which the early Christians engaged. With such worship, though in more elaborate form, the Church had always been familiar, for as Christianity itself was in so many respects the fruit and outcome of Judaism, the expansion, into principles of world-wide and perpetual application, of truths that had hitherto been national and local, so its worship and organization were, in large measure, the adaptation of familiar forms to those simpler and more comprehensive ones of the New Testament Church. Throughout the successive periods of Israel's history, marked by patriarch, psalmist, and prophet, Divine worship had grown from simple sacrifice at a family altar to an elaborate temple-ritual, in which praise and prayer and the reading of the Law occupied a prominent place; to this were added in later times the exposition of the Law and the reading of the Prophets. This service, elaborate with magnificent and imposing forms, continued in connection with the Temple worship down to the time of our Saviour, while in the Synagogue a simpler service, combining all the essential parts of the former with the exception of sacrifice, was developed during the period subsequent to the Babylonian captivity, when, as is generally conceded, the Synagogue with its service had its origin. Apart then from the ritual connected with sacrifice, which was wholly typical, the temple service and the simpler worship of the Synagogue were identical in their different parts, although differing widely in form. Now, just as Christianity was itself not a substitute for the Jewish religion but a development and enlargement of it, so Christian worship was an outgrowth, with larger meaning and broader application, of the worship of God which for centuries had been conducted among the Jews. It continued to comprise the essential elements of prayer and praise, together with the reading and exposition of the Divine message, a message which was enlarged in Apostolic times by the record concerning the Christ who had come, and by the inspired writings of the Apostles of our Lord to the Church which they had been commissioned to plant and foster, while associated with these was the administration of the Sacraments of Baptism and the Lord's Supper. It has always been maintained by the Presbyterian Church, that of these different elements of worship, none should be neglected, inasmuch as all of them have Divine sanction, and that to these nothing should be added, inasmuch as any addition made, could possess human sanction only, and would be a transgression of the principle that Scripture and Scripture alone contains authority for the government and practice of the Church of Jesus Christ.