Most things you get from the store comes with some sort of instruction manual. Whether it is the set up to software, a toy, telephone or some other item, if there is any sort of assembly, start up, or usage of the item, there will usually be some set of instructions that come with the item. All of us have heard the humorous stories about people that attempt to assemble or operate something without having read the instructions.
We also have an instruction manual for life. Not only does it tell us how to do it, but it also tells us purpose and nature of life and the world around us. It has a blueprint for all of life. It tells us where life comes from, what the nature of humanity is, and what humanities relationship is to nature and to the creator. Like the physical order of our world, there is also a moral order. When we violate the physical order, there are consequences. We don't jump off of cliffs or put our hand in the fire. That is the way the creator has constructed the world. In the same way, there is a moral order as well. When we violate the moral order, there are also consequences.
The original violation among humans happened in the first few chapters in Genesis. The results were disastrous and we are still seeing the effects of it today. But God has given us help on many different levels. God sent his Son to defeat sin and death. God has also granted us his written word as an instruction manual to guide us.
But God's word is much more than this. Not only is it a lamp to guide our feet, it is also a tool of inner transformation. God's word is living and active. It has the power of transformation in our life. It is able to lay our innermost selves bare so that we can be evaluated and transformed (Heb 4:12). It is like a mirror that reveals who we are and what we can become (James 1:23). It is "God-breathed" (2 Tim 3:16). God breathes new life in us through the words of life. It is the sword of the Spirit (Eph 6:17), which is the tool the Spirit uses to keep us from being overcome by the world. Wisdom comes from the word of God (1 Cor 2:13), and it is wisdom that helps to discern the most important things in life and how to navigate through them.
But this does not happen automatically. Merely reading the words does nothing. Memorizing scripture is better, but even this will do nothing. What is necessary is acceptance of the word in faithful obedience. Those who read the word and do not accept or act on it are like the demons that believe and shudder (Jas 2:19). They know the truth, but they do no act on the truth. God's desire is not merely for us to know scripture, but for us to know Him, to be in submission to him, to please him. Scripture is one of the tools for us to know God and guides us in our submission to him.