In just a few verses of St Paul’s letter to the Philippians (4:4-9), we learn how to acquire the peace of God as well as communion with the God of peace.
To get the peace of God you need to do four things: Rejoice, give up anxiety, pray, and give thanks. These may not always seem to be easy to do (especially giving up anxiety, right?), but there is grace at hand to help us, for he says, “The Lord is near.” That awareness alone ought to be enough for us to begin practicing the four things in earnest. And the word of God bears within it the Spirit of God, so that it is able to accomplish what it says. If you still have anxiety, then go back to the third thing: pray. But you have to pray with thanksgiving, for the Lord is near. If the Lord is near, that is cause for rejoicing. And if you are rejoicing and praying with thanksgiving, then there is no place for anxiety, is there? Therefore “the peace of God, which passes all understanding, will keep your heart and mind in Christ Jesus.”
Only two things are required to get the God of peace to be with you: think and do. Those are pretty general things, so the Apostle tells you what you ought to be thinking about and doing. “Whatever is true, whatever is honorable, whatever is righteous, whatever is pure, whatever is worthy of love, whatever is gracious; if there is any excellence [literally, virtue] or anything praiseworthy, think about these things.” Reflect upon the things that tend to fill your mind. Do they fall into the above categories? If not, then you are keeping the God of peace away from you. God is found where truth, honor, righteousness, purity, love, virtue, etc, are found. So think about these things, rest your mind in them, let them strengthen and purify and ennoble you—and let go of all the base, corrupting, superficial or ungodly rubbish that is always being offered as junk food for our minds. We were made for greater things.
If you are thinking the right things, what should you then do? “Whatever you have learned and received and heard” through the writings of the Apostles and the teachings of the Church and your meditation on the good and true and beautiful. Act accordingly, and the God of peace will be with you.
It is perhaps a rather challenging discipline to do the four things and the two things. Yet it’s not all that difficult. You just have to really want to. You have to be willing to make the effort to give up what is not of God and to embrace what is. It’s really good for you, after all, and it will (as you’ll notice, if only little by little) even make you happier. You will have the peace of God and the God of peace. So rejoice!