Signs and Fear in Psalms

According to St. Augustine a sign is something that signifies something and "makes some other thing come to mind." (30) He also writes that fear of God is learning His will; becoming aware of our sins and deciding to live in a way that is more like Christ (God). St. Augustine illustrates this by writing, "...nailing our flesh to the wood of the cross as it were crucify all presumptions." (33) The Holy Scriptures are signs of ideas or ways to live life, they point to the will of God, which ultimately lead to God. Christians should live in a way that they know the scriptures and what they signify for them. This is the fear of God Augustine is talking about. Because you fear God, that will lead you to reflect on yourself and your deeds (evaluting life according to the scriptures).
The question is where exactly does the book of Psalms fit into all of this? Well the Psalms are a sign in and of themselves and there is certainly a lot of fear of God present in the writing. Many times when we think of Psalms, we think only of the pleasant ones (i.e. Psalms 1, 23, etc.) and that's all. St. Augustine would find a problem with this because he believes that it is our duty as Christians to become familar with and analyze all the scriptures, using them to interpret one another. (37) The Psalms represent both reward and punishment for either following or not following God. They also signify communication with God (prayer), seeking God (Ps 13), seeking help and comfort (Ps 61), and seeking forgiveness/repenting (Ps 51). The Psalms also represent signs of praising and worshipping God (Ps 136). Fear is present throughout the book. The writers constatntly show the fear the people (Israelites) had of God leaving them, hiding from them. They write things like "Why has thou forsaken me," and "Why do you hide yourself from me?" This types fo things are usally followed by the people commiting to God's will and vowig to follow it, if He shows up and helps them. This is shown in the Psalms with statements like, "And I will sing praises to your name forever." There are also things that promises God that HIs word/way will be spread if He blesses His people (Ps 67). The Psalms show how knowing God is fearing God. In the book God's people called upon Him all the time, they gave themsleves to Him because they knew that they couldn'y make it on their own.
To go back to St. Augustine, he breaks signs into two categories, literal and meaphorical. (37) These are the two ways in which the Psalms can be interpreted. When they were first written, the things in them (war, specific problems) were pevalent to the believers of the time, namely the Israelites (i.e. war, physical enemies, etc.). In their historical context, the Psalms were and could be literally interpreted. Today the Psalms are more commonly used as metaphors for spitiual warfare and how God will help you fight these battles. War Psalms and those stating specific problems are the ones that are most generalized and interpreted in a metaphoric way.