I bet you’ve had a busy week.  If you’re like most folks, it’s go, go, go.  Work, church activities, ball games, doctor’s visits, household to-do lists, school projects, and the general rat race of life have set a pace that can easily leave you out of breath.  Then there may be the pressure of bills, car repairs, deadlines, chronic illnesses, or relational conflicts that are draining your emotions dry.  And on top of all that, Satan is alive, well, and still very active; the world is still pulling on you; and your flesh is still rearing its ugly head from time to time, all of which may be taking their toll spiritually.  You’re tired.  You feel it.  The “low fuel” light has lit up on the dashboard of your soul.  No matter who you are or how strong a Christian you may be, it could happen and perhaps is happening to you now.  But it doesn’t have to defeat you.  A simple thought in Isaiah 40:30-31 gives the remedy.  “Even the youths shall faint and be weary, and the young men shall utterly fall: but they that wait upon the Lord shall renew their strength….”  Look at that word “renew.”  Its idea is to “pass on, change.”  The word is used throughout the Old Testament in reference to changing clothes.  In other words, it has the idea of exchanging one thing for something else.  Now apply that to your situation.  The secret to making it through the days that drain you is to simply exchange your strength for the Lord’s.  No, you can’t keep up, stay up, or power up on your own.  You must look expectantly to (“wait on”) the Lord and say, “Trade you!”  Exchange your cap gun for His cannon.  Turn in your tricycle for His tractor-trailer.  Give Him your feeble attempts for His faithful assistance.  Trade your incompetent stumbling for His omnipotent support.  Do it every day.  Refuel.  Refresh.  Renew.  It works!