The Lord's promises are gifts to His children, and He absolutely loves to help, teach and give gifts to us. Remember, He created us for His pleasure. (Revelation 4:11)
In the beginning His first children (Adam and Eve) had everything and anything at their disposal. They lost it all because of their disobedience to the Lord's loving instruction to stay away from what can harm them. The root cause of disobedience is lack of trust. It only took the smallest seed of doubt to be put into their minds to cause the bond of trust to be broken between the Lord Yahweh (proper name of God) and His beloved children. (Genesis 3:4) Hence the world we live in today.
Throughout the entire Bible the Lord Yahweh continually preaches and pleads to us to trust Him. When He became flesh He very thoroughly demonstrated to us, how His children are to trust Him (no matter what).
Having trust/faith in our Heavenly Father Yahweh is not something to be taken lightly. It is the key to restoring our relationship and bond with Him. Just as it took a small seed of doubt to break our bond and set us on the wrong path; it only takes trust the size of a mustard seed to put us back onto the right path.
To use your shield properly, read the Bible verse that coincides with the prayer on your shield. Understand that the Bible verse is Yahweh speaking to you. Now speak the prayer over yourself and use it as an opening statement or an ice-breaker between you and your Father. Pay attention to the conversation you had. Watch and learn throughout your day regarding that conversation and remember that He is a great teacher and loves to teach. Let your relationship with Him grow and you will be absolutely amazed!