Remember the first time you spoke in public? If you were nervous, the teacher told you to picture everyone in their underwear. That way, you'd be laughing at everyone instead of fearing them. Knowing you were fully clothed, and nothing you said from here on out would be more worthy of laughter than what they looked like underneath their fashionable (or not) attire.
"Little children, you are from God and have overcome them, for he who is in you is greater than he who is in the world." 1 John 4:4 ESV
When we start to feel the least bit small or don't think you have what it takes. When others are flaunting their stuff around you and it's starting to get to you just a little bit. When your situation doesn't seem to measure up to someone else's; just picture this. You are walking a VERY big dog if you are in Christ. God wants you to have such joy in Him that your heart grins as the deep peace that He bought for you seeps through your soul and anything coming from the world just looks like a little purse dog in comparison!