I love the passage from Isaiah 50:4 which was lifted up at BroGreg's Blog today. I've molded a sermon from this passage, as well as lifted it up for contemplative prayer.
What I find special about this passage is that it preceeds the prophetic words of Isaiah prior to one of the servant songs in that book. There are deep, meaningful words in this passage. Having a learned ear to hear, and a taught tongue to proclaim, very good, and very applicable, and very deep indeed.
I urge anybody who is seeking something to preach about to go to Isaiah 50:4, and glean inspiration.
What a wonderful OT passage that applies today, to this very world in which we minister and pray for guidance.