"Just leave it in God's hands." I hated that phrase...and it was used a lot as I grew up in the church. What exactly does that look like anyway? I didn't get it. I knew about prayer, I prayed, but sometimes the Christian-ese just didn't suffice. Something sounding a little like Carrie Underwoods's Jesus Take the Wheel echoes in my mind.
So what taught me to stop worrying and to trust God with my concerns? Reading Scripture. Memorizing Scripture. Hearing Scripture by great pastors, teachers, women's group leaders, video studies, etc. The Holy Spirit makes the Word of God alive to us and in us. The truth of it sinks down into our souls when we know it. The Bible is sharper than any two-edged sword and it's that word that assures us the Lord has our lives in His hands. There is nothing to fear or be anxious for when we know we can pray with the stories, poetry, prophesies, teachings and letters of Scripture to remind us we're not alone. God's got our backs and our present and our eternity are safe with Him. I'm certainly not a perfect example of peace and rest during difficult times, but in the depths of my soul I get it now. There is really no sense in fretting when I humbly tell the Lord that I can't do this thing on my own and I'm trusting Him to be in control. His way is the best way and somewhere in that tunnel is a Light that will get me exactly where I need to go in this life--He's got the wheel.
"Be anxious for nothing, but in everything by prayer and supplication, with thanksgiving let your requests be made known to God." (Philippians 4:6)
"But the Helper, the Holy Spirit, whom the Father will send in My name, He will teach you all things, and bring to your remembrance all the things I said to you. (John 14:26)