I know many believers who live much in the Psalms of the Bible.  Sadly, as opposed to centuries ago, they do not have the relevance to much of Christendom and the Christian life as they ought. The singing of inspired Psalms in Worship for instance, is often superseded and replaced, by uninspired,  words of men in hymns. So at once is made void the words of Jesus, in John 4:24, to worship Him in Spirit and in truth.

But even away from the setting of worship, the Psalms have great, great value.  They are one of the most comforting books for the afflicted believer, and one of the most encouraging.  They also, will help us to learn how to pray. As these Psalms which were the prayers of David and others, are a pattern for prayer, no less than The Lord’s prayer in the New Testament.

The books of the Old Testament are often relegated in favour of New Testament only; yet the Psalms are full of Christ in every way. This book, in itself, gives validation to how the Old Testament has just as much worth to today’s believer as it ever did, because just like the whole of the Old Testament is full of shadows of Christ, you cannot read the Old Testament without reading of and seeing Christ, this book perhaps above any other it is also true. Psalm 22 being an excellent example.

Our predecessors, of those who have gone before us, also knew the value of the Psalms, and appreciated them greatly and studied them devotedly.  Here is just a few short quotes, from names in Christian history, and their words apply as much today, of why the Psalms still have such value to us, as New Testament Christians.

Although all scripture, breathes the grace of God, yet Sweet beyond all others is the book of Psalms History instructs, the law teaches, prophecy announces, rebukes a Chastens, Morality persuades, but in the book of Psalms we have the fruit of all time, e and the Kind of medicine for the salvation of man.
–Ambrose of Milan

The Psalter is a little Bible, and the Summary of the old Testament, 1 verse of the Psalms is sufficient for the meditation of the day, And he who at the end of the day finds himself fully possessed of Its Sense and spirit, may consider his time well Spent
- Martin Luther

The book of Psalms I call an anatomy of all parts of the soul, For there is not an emotion from which anyone Can be Conscious that is not here represented as in a mirror The holy spirit has drawn here to the life, all the griefs, sorrows, fears, doubts, hopes, cares, perplexities-In short, all the distracting emotions with which the minds of men are usually agitated. There is no other book, in which are recorded so many deliverance’s, nor one in which the evidences and experiences, of the Fatherly Providences of God, are celebrated with such splendour of style and language, and yet with the strictest adherence to the truth.
-John Calvin

We have now before us, one of the choicest and most excellent parts of the old Testament, nay, So Much is there in it of Christ and of his Gospel, as well as of God and his law, that it has been called the summary of both Testaments.
Matthew Henry