There has been a box of brand new pens on my shelf for several years, and every few months I pull another out. (Pens just seem to disappear around the office.) A few days ago, I pulled the last pen from that box. It was dried out. After 
several seconds (and pieces of scrap paper) of making circles, it finally came to life and is now operating as it should.
That got me to wondering. How many Christians are there who have been “sitting on the shelf” for a while and are all dried out? It’s been a long time since they started a conversation with someone about Jesus. It’s been a long time since they sat across the table from someone and taught them the gospel. It’s been a long time since they invited brethren into their home for fellowship. It’s been a long time since they did much of anything in or for the church.
If God were to pick you up off of His shelf and need to use you right now (cf. Rom. 6:13), would He find you ready for immediate service or would He find you dried out? Think about it.