The attempt to detect Theology in the linguistic deviations and divergencies of the Septuagint (LXX) with the Massoretic Text (MT), presupposes the use of certain exegetical methods. Of course, this implies methods to be used by the modern Septuagint scholar and not the hypothetical translation technique(s) used by the LXX-translators. Therefore, I suggest the scholar should integrate the historical critical method - in a balanced manner, without the incriminating questioning of long outdated historicism - into the modern LXX-exegesis. In this way, I think, we have the opportunity to verify or falsify hypothetical exegetical practices probably used by the LXX-translators and to discover where we are really able to talk about genuine Theology in the LXX - in contrast to the MT. The LXX-Psalm 150, in comparison to other related Old Testament texts, was chosen to exemplify this suggestion.