What is your giant? Are you facing a crisis? Is it a problem at home, at work, or in your family? The only way to face a giant is to do as David did: remember the lion and the bear. By remembering God’s faithfulness to him in his past crises, David could go up against Goliath without fear.
How Discouragement Enters
Every person with a vision from God will have serious opportunities to become discouraged as they reach for the fulfillment of their vision. 
Indeed, just as Israel was given a promise from God and provisions to help their return, so the Almighty has given promises and provisions to us. Your vision may be for your personal transformation, or it may be a God-inspired desire to see your family or church brought into spiritual renewal.  You may even possess a citywide vision or a holy passion to see your nation turned toward God.  Yet, like the Jews, we can be just as vulnerable to discouragement and its effects. 

How does discouragement gain access to our souls? The answer is simple: We start evaluating our lives based upon information compiled by our senses instead of assessing our position based upon the promise and help of God. 
However, I don't mean we are unaware of the difficulties of our faith assignment, but that God is good and He is not hindered by our present limitations.

When David volunteered to fight Goliath, in 1 Samuel 17:33-36, Saul said to David, "You are not able to go against this Philistine to fight with him; for you are a youth, and he a man of war from his youth."  But David said to Saul, "Your servant used to keep his father's sheep, and when a lion or a bear came and took a lamb out of the flock, I went out after it and struck it, and delivered the lamb from its mouth; and when it arose against me, I caught it by its beard, and struck and killed it. Your servant has killed both lion and bear; and this uncircumcised Philistine will be like one of them, seeing he has defied the armies of the living God." NKJV

David knew the danger he was facing against Goliath. He wasn’t some novice, a naïve kid full of himself and looking for a fight. No, David was simply remembering his past deliverances. What God did for him! And now he looked his enemy squarely in the eye and stated, "The LORD, who delivered me from the paw of the lion and from the paw of the bear, He will deliver me from the hand of this Philistine." 1 Samuel 17:37 (NKJV)

What are we remembering and focusing on?
Facing the giants in life and being able to have victory, comes only by remembering the lion and the bear. It comes when you’re able to recall the incredible faithfulness of God, and the past victories he has given you. You can’t face a giant until you’re able to envision and understand the majesty and glory of God in your life.
We are an open book to the world around us. What we do and say. We are always imparting something. Faith or fear! You parents and even if you are not a parent, what we impart is critical. Our passion for God, our insight into the supernatural, is paramount to where the next generation will go.
Listen, your passion for God, those you come into contact with in unity and purpose and focus. What you pass on to them has the capacity to exponentially increase what you carry. David passed on faith and raised up giant killers.