Reading from the Book of Hebrews 4:1-2...
1 Therefore, since the promise of entering his rest still stands, let us be careful that none of you be found to have fallen short of it. 2 For we also have had the good news proclaimed to us, just as they did; but the message they heard was of no value to them, because they did not share the faith of those who obeyed.
Those who did not listen to God's Word or obey His instructions did not enter into the place of rest He offered to them. So when you feel frustrated or upset, or if you lose your peace and your joy, ask yourself, "Am I believing God's Word?" The only way we will ever be free from struggling is to believe the Word and obey whatever Jesus puts in our hearts to do. Believing God's Word delivers us from struggling so that we can rest in the promises of God.
Experiencing His rest is one way you can tell whether you are really "in" faith, or whether you are just trying to "have" faith. When you truly enter into the realm of faith, you enter into the rest of God.
Rest is freedom from excessive reasoning, struggle, fear, inner turmoil, worry and frustration, which develop because of our working to do what only God can do. Being in God's rest is not necessarily resting from physical activity, but resting in confidence in the midst of everything that goes on in life. It is the "rest of the soul" where the mind, will, and emotion are at peace.