When we think of rejoicing, what comes to mind? Births, weddings, parties, and wins! We may be excited, we may celebrate, and we may have fun, and yet, all of that could happen in the context of worldliness and of the flesh, but that would not be rejoicing. In the realm of spiritual truth, rejoicing is always focused on God. I may be excited for a vacation, I may have fun at a birthday party, I may find pleasure in a lazy Sunday afternoon, but if I am to rejoice in it, then I am going to need a heart set on God in my vacation, or party, or lazy Sunday afternoon. All joy comes from God, and from God alone!
In this Psalm we are given three, often repeated in scripture, reasons that we can rejoice in God and offer Him all the glory and praise! He is worthy of it all!