This topic is found in the series Journey of Faith by Liguori Publications. This particular topic (C9) is most commonly called salvation history and refers first of all to the events and people of the Hebrew scriptures from the time of the Patriarchs up to the time of the return from Babylon and the events detailed in the book of Maccabees. Taken by itself salvation history can seem to be simply a quaint and often trivial recitation of events long past. However, when looked at in the context of a few of the themes of our faith we can see the importance of being acquainted with the central events of salvation history.
First of all, it is useful to see salvation history as a sort of journey. We use the theme of journey often. We speak of the faith journey of individuals and we refer to the RCIA as a journey of faith. In our faith lives we are called to journey from our initial encounter with God to greater and greater faithfulness to God until we reach our final destination (heaven). In the same way, salvation history describes the struggles of the people of Israel to live in faithful covenant with their God. The image of journey is even more explicit in the book of Exodus where the people literally journey from slavery in Egypt to the Promised Land. On this journey they go through the same struggles of trying to live in faithful covenant with their God who had done so much for them.
So, when I am on my own journey I am not alone. I walk in the footsteps of those many people in salvation history going all the way back to Abraham who made the same journey before me. I am also not alone since I journey with all of the people of God who are currently making the same journey. This has many implications. First of all, I can follow the trail left for me by my ancestors in the faith. I know the paths they chose and the dangers they encountered. This means that the traditions of my faith have the ability to guide me. Secondly, the importance of staying with the group seems clearer. During the journey I can sometimes wander off the path to explore (I have a certain amount of religious freedom). But there are danger points where I need to follow more closely with the group. These are areas where I might clearly separate myself from the group. (e.g. A Catholic denying the divinity of Christ would be departing from the beliefs of the Church in an important way.) Another danger comes when I take up beliefs that the group (the church) has clearly rejected in the past. This means that the teaching authority (magisterium) of the Church has the ability to guide me. For me these are two obvious implications of thinking of my spiritual life as a journey.