When travelling through an unfamiliar city or a strange forest, most people have some sort of help. Some use a map, other a compass, and still others a guide. None of these things alone will guarantee that a person will get where they want to go, and lacking these things will not necessarily prevent a person from arriving at the desired destination. However, when a person has all of these things, he or she has the greatest chance of getting where he or she wants to go. Just as a person travelling through an unknown area has these tools, we are given similar tools to get through life.
Perhaps the most useful tool for a lost traveller is a map. The good news is that we are provided with a map for our lives; it's called the Holy Bible, and it is the most complete map ever made. Following this map will certainly move you towards your desired destination.
The bad news is that there are a lot of cheap versions of our map, and a lot of counterfeits. These counterfeits and cheap maps contain some of the "right" informations, but also a lot of misinformation. Sometimes a road or a path is not shown on the map, other times it's in the wrong place. These maps include such books as the Talmud and the Qur'an, as well as such additions to the Bible as the Gospel of Thomas. Though they may contain some useful bits of information, these "maps" are more likely to simply get you more lost than before.
Many people prefer to use a compass to determine which direction to go. Fortunately enough, we all come with a sort of built-in compass: our consciences. Just as a compass points North, our consciences will always point towards doing what is right. However, just as it is only helpful to know which way is north when you know which direction you need to go, the conscience is only helpful when your sense of "right and wrong" is correct. In other words, if you don't know where you're trying to go in relation to where you are, knowing the direction in which you are going is not really very helpful.
Often when travelling in an unfamiliar area, we will use the services of a guide to help us find our way. This is especially true if our map is as complex and complicated as the Bible often seems to be. The matrix of streets and the tangle of paths presented in life are often so complicated that only a well trained eye can help unravel them. At other times, a pair of streets may lead to the same destination, but one is typically more crowded with traffic than the other; again, the advice of a guide may be well apreciated.
It just so happens that such a guide exists. In fact, many do: our family, our friends, and our religious leaders, the Church. Some of these people may have had experience with a particular problem that you are facing. Other may have a strongly developed sense of moral clarity. Still others have studied our map and have travelled the paths and streets that it presents many times, knowing which ones are usually safest and which have the least "traffic." In particular, the Church has 2000 years of experience behind it, and when acting with the wisdom gained from that experience will seldom lead you astray.