I just read this devotion on Our Daily Bread: http://www.rbc.org/devotionals/our-daily-bread/2008/03/03/devotion.aspx

It referred to a lot of the stuff we have been reading about how the Israelites complained so much, and told a story of a pastor who challenged his congregation not to complain for 21 days! That sounds like an excellent exercise- I imagine you could change a lot in that time, and I think we all need to do less complaining. Look what happened to the Israelites when they complained.

I wouldn't be surprised if anyone deciding to do this challenge finds something especially frustrating or annoying happen to them during that time period but I think anyone who feels like this exercise could really help them should think about giving it a go, even for a day or a week. We have learned a lot from the Israelites about what a complaining attitude does among God's people and how it upsets God, so I thought this devotion was quite relevant!

That's an interesting challenge that that pastor gave. I'd probably flunk the no-complaining challenge within an hour, knowing me