How many have seen a fishing bobber? Fishing bobbers are usually round and made of either plastic or foam, and are made to float on top of the water. They will usually float no matter what. You have to add weight or really pull on it to keep it under water. The more weight or the harder you pull, the easier it is to keep it under the water. If you try to push it under, it will try roll out from under your hand and resurface.

We should live our lives like that bobber. Whenever the world tries to push us down, we should roll out from under it, and resurface.

Ephesians 6
13Therefore put on the full armor of God, so that when the day of evil comes, you may be able to stand your ground, and after you have done everything, to stand.

It is when we let the world get us down, and when we add weight to our lives - fear, worry, doubt - that we start to get pulled under the water. Once we get pulled under, we must cut the strings or we will get pulled down to the bottom. How do we cut the strings?

Matthew 11
28"Come to me, all you who are weary and burdened, and I will give you rest.
29Take my yoke upon you and learn from me, for I am gentle and humble in heart, and you will find rest for your souls.
30For my yoke is easy and my burden is light."