The Psalter constitutes a collection of texts from different periods and with various preoccupations. We can distinguish some psalms that have an independent origin, before the construction of our current Psalter, and some literary psalms linked with the constitution of the Psalter. An intermediary stage was the constitution of some collections, with the Davidic psalters, the Coreitic psalter, and the Asaphite psalter. The constitution of the Davidic psalters has a link with the overall structuring of the Psalter around the hope placed in the Davidic Messiah. This aspect has enabled psalms with very different perspectives to be incorporated within the framework of the messianic issue, by the use of "titles" which generally infer some verbal connections with the Books of Samuel. The final drafting of the Psalter must be understood on the basis of an inclusion system. The central part of the Psalter, which is fundamental to the messianic issue, even if the word "Messiah" is never used, is made up of the Elohistic psalter, Ps 42-83, an artificial yet highly symbolic construction with the use of the number 42. After the disappearance of the Davidic Messiah (Ps 89) and his replacement by the priestly Messiah (Ps 84,10), the alliance with the patriarchs take the place of the alliance with David (Ps 105). In the end, David is reinstated as founder of the temple cult, in relation to the transfer of the arch to Jerusalem. One final wise piece of editing has not modified the structuring of the Psalter.