The Psalter as a gift for worship cannot be overemphasized. It has been a resource for God’s faithful people since ancient times. We know that Jesus prayed the Psalms in synagogue which in fact testify to Himself. It is likely Luther as well had the complete Psalter memorized, as was the custom in the monastery. The Psalms are a great teaching tool in the Old Testament. The idea of Lex orande Lex credende would make the psalms essential to harmonize prayer with proper belief and theology. For the Lutheran theologian there is no speculation. God has defined himself, his work, and has defined us. God has given us also the language to communicate with Him through His very Word of which the Psalter is of such benefit. My personal experience with the psaltery and speaking about the psalms with one another has made this clear. Our spiritual, emotional, and theological vocabulary is set before us in what Luther calls the "mini Bible." In worship these songs are either sung directly, antiphonally, or in a responsorial order. We study and sing the Psalms that we might teach, pray, and suffer in faith with David in the mighty ark of the Church.