"Purify yourselves for tomorrow the Lord will do wonders among you."
Your potential is determined by your purity. If your motives are pure, there is nothing God cannot do through you. Instead of focusing all of our energy on planning the future maybe we ought to focus on purifying ourselves. After all, that is how God prepares us. You want to be used by God? Purify yourself. You want the favor of God? Purify yourself. You want to experience peace and joy? Purify yourself. You want to see God do wonders? Purify yourself. Or maybe I should say: let God purify you. You can't do it yourself. But Christ has done it for you on the cross.
The way you prepare yourself for tomorrow is by purifying yourself today!
How? It starts with repentance. If you confess your sins, He is faithful and just to forgive you your sins and to cleanse you from all unrighteousness. Confession is spiritual cleansing. Purity is a deep cleaning if you will. It involves the deep recesses of your heart and mind. It includes the hidden motives of your heart. It includes the secret thoughts in your mind. You have to look in the mirror for a long time! You have to be brutally honest. You have to give God all access to everything. But if we make purity our goal, God will do wonderful things! That is the Biblical pattern.
By the way, that probably means we'll go through some painful things. Purifying always involves some fire. But God redeems our pain and uses it for His gain! And it's the painful things that makes the wonderful things so wonderful.