A couple of Calvinists debate the regulative principle of worship. Does the Bible teach that Psalms are the only worship songs that should be allowed in the church? No, but some people still hold to that position. They like to use Deuteronomy 12:32 as a proof text, which only leads me to wonder what the people of God sang before the Psalms were written.
If we believe in election, why should we preach the gospel? Spurgeon's answer: "God has called me to preach His word and if I knew that all the elect had a yellow stripe painted down their backs, then I would give up preaching the gospel and go lift up shirt tails!"