"Do not be anxious about anything, but in everything by prayer and supplication with thanksgiving let your requests be made known to God. And the peace of God, which surpasses all understanding, will guard your hearts and your minds in Christ Jesus." - Philippians 4:6-7
Years ago, a friend introduced me to the American adventure writings of Louis L'Amour. My friend told me to note two things in each story. First, he said that L'Amour always has a good guy, a bad guy, and a girl. Second, he said that L'Amour always has the good guy sit with his back to the wall in saloons and taverns because the good guy doesn't want anyone sneaking up on him.
It's the second concept of "back-to-the-wall" that's connected to today's Bible verse. Basically, God is telling us that he wants to "guard our hearts" both by giving us peace and also by keeping us from anxiety when we tell him in prayer what we see in front of us.
The reason God wants us to tell him in prayer what we see in front of us is because God is covering everything that's behind us. God has our back! God's literally covering our rear, just as God tells us in Isaiah 52:12, "For you shall not go out in haste, and you shall not go in flight, for the Lord will go before you, and the God of Israel will be your rear guard."
No "haste" and no "flight" equals no anxiety because God is leading us forward and guarding our "rear."
So practically speaking, what does this all look like?
First, trust God's promise that God has both your back and your past covered. Stop looking over your shoulder, and let go!
Second, trust and obey God's command, "with thanksgiving let your requests be made known to God." In other words, thank God for dealing with your stuff even before you ask, and then tell God about everybody and everything that you can see in front of you.
Finally, experience God's peace, and listen for God to speak to your heart. Doesn't it make sense? If God has your back, and if you've told God about everything in front, then everything is in God's hands! And if it's all in God's hands, then what is there to worry about?!?! Nothing.
There's only peace, coupled with the voice of God speaking to your heart with words of life.