It is a maxim worth repeating often and few pastors have said it more clearly than Paul Tripp:

"As a person made in the image of God you don’t live life based on the cold, objective facts of your experience, but on your interpretation of your experience. Everyone living is a philosopher and a theologian. We’re always stepping back, taking a look at our lives, and turning our situations and relationships over and over in our hands for further inspection and understanding. The sense you make out of the events of your life will form what you do and say in response to them. As you interpret new events and reinterpret old events, your interpretations will begin to form a worldview that will function as an organizing structure not only for what you think, but also for how you live."

To put it another way, one of the great dangers you face in life is not the events and circumstances of your life but how you interpret those events and circumstances. 

This is vividly portrayed in Peter when he boldly prepared to keep Jesus from going to the cross. "Far be it from you, Lord! This shall never happen to you" (Matthew 16). But Jesus rebuked him, charging Peter's interpretation of events as being more in league with Satan than with God.

Peter clung to his own interpretation of Christ's sufferings right up until Jesus' arrest in the garden where Peter took a sword and severed a soldier's ear from his head (John 18:10). Without an intervention of grace, Peter's commitment to his own interpretative framework of the ways of God in Christ was quickly leading him to become a harden, embittered Cross-despiser. But God intervened. Peter was saved and changed.

The brings me to the other half of the point - the inverse of the above is also true: one of the great sources of encouragement in life is not the events and circumstances of your life but how you interpret those events and circumstances.

This is vividly portrayed in Acts 5. Right after the apostles are beaten by the temple guard and commanded not to speak in the name of Jesus, we read: "Then they left the presence of the council, rejoicing that they were counted worthy to suffer dishonor for the name." The apostles very personal experience of life, though painful and thick with the malice of others, was not determinative of how they responded. Something else was - their interpretation of their experience! They saw their sufferings as a testimony of their love for Christ who, after suffering obediently unto death, was highly exalted with the name that is above every name (Phil. 2:8-10).

What is the interpretive key in these two situations, Peter's in Matthew 16 and the apostles' in Acts 5? It is the gospel, that covenant of grace, that promise of God to be the Redeeming Savior of sinners who trust in Him.

When Peter was despising the sufferings of Christ he was interpreting his experience without the light of the gospel. When the apostles of Acts 5 were rejoicing having just been beaten and threatened (a transformed Peter now among them) they were interpreting their experience with the light of the gospel.

The light of the gospel of God's redeeming grace makes an enormous difference in how you experience life. The difference is not a change in your on-the-ground circumstances. The difference is a radical change in your interpretation of those circumstances, a change as different as the truth is from a lie.

When because of unbelief the light of the gospel is off, your interpretation of life will become increasingly dark and foreboding. As you grow older you will start to discover that your life experience with marriage, children, career, money, family, friends, and health have not prospered as you had hoped. Without the light of the gospel you will chase one oasis-of-happiness after another, trying not to fall headlong into whole-scale disillusionment, disappointment and despair. You will eat your way, entertain your way, drink your way, shop your way, consume your way, indulge your way, or hate your way through life in an effort to stave off the deepening sense that your life has not achieved the glory you demanded of it. And without the light of the gospel, God himself will become your greatest disappointment because He has not delivered you from the sufferings and messes of this one life you have to live.

This is the way of unbelief and of unbelievers. This is the way of interpreting life with functional ignorance of that rule of grace that presides over the children of God in Christ. This is the way of interpreting life as if there is no way to glory through suffering, as if there is no living Lord who assigns trials to His beloved children to display His glory as they refuse to curse Him because they trust His promises are better than life. This is the way of interpreting life as if the grain of wheat does not need to go into the ground and die before it brings life (Jn. 12:24). Interpreting your life without the light of the gospel is interpreting life without the life of Christ crucified for sinners and raised to rule in grace and peace.

But there is another way to interpret life, in the light of the gospel.

When the light of the gospel is on, your interpretation of life becomes increasingly controlled by the greater narrative, the one outside the bare facts of your own circumstances. When the light of the gospel is on you see all things, receive all things, bear all things in the certain knowledge that God is for you and so nothing and no one can be against you. If God "did not spare his own Son but gave him up for us all, how will he not also with him graciously give us all things?" (Rom 8:32). This is the astounding reorientation that the gospel of our justification brings to our daily lives. The announcement of "Grace and peace to you from our Father and the Lord Jesus Christ" rises like a sun over every day just as it stands over every apostolic letter in the New Testament. Christ's rule of grace and peace for those who trust the promises of the gospel means that no trouble in marriage, no trouble with  children, no trouble with work, no trouble with money, no trouble with health, no trouble on the world stage or even with the wind, the rain and the waves can ever be interpreted as working a scheme against God's grace to you in Christ. .

By the gospel you interpret all of life's troubles, conflicts, disorders, afflictions, and deprivations as God's assigned trials, where He gives you your share in Christ's sufferings so you learn to trust Christ for the hope of the glory to come knowing that His own perfected sufferings for sin and among sinners did not keep Him from glory. Such faith and lively believing of the gospel interprets all your experience of life in the light of Christ's own sufferings and victory. Having seen the eternal Son attain to His glory by overcoming all temptations - temptations to sin, temptations to disobedience, temptations to abandon His calling, temptations to bring only wrath, temptations to break the covenant - we learn how much the children of God can trust the Father of our Lord Jesus Christ to deliver us. And so begins a flow from us toward the world of that life that flowed from Him toward us sinners - grace and truth instead of rage, self-indulgence, and self-pity.

For what we proclaim is not ourselves, but Jesus Christ as Lord, with ourselves as your servants for Jesus' sake. For God, who said, "Let light shine out of darkness," has shone in our hearts to give the light of the knowledge of the glory of God in the face of Jesus Christ. But we have this treasure in jars of clay, to show that the surpassing power belongs to God and not to us. We are afflicted in every way, but not crushed; perplexed, but not driven to despair; persecuted, but not forsaken; struck down, but not destroyed; always carrying in the body the death of Jesus, so that the life of Jesus may also be manifested in our bodies.
For we who live are always being given over to death for Jesus' sake, so that the life of Jesus also may be manifested in our mortal flesh."  - 
2 Corinthians 4:5-11