Randy Alcorn was interviewed on his updated book The Treasure Principle. In this audio clip, Randy talks about tithing as a New Testament Christian.

Why I Don’t See Tithing as the Pinnacle of Christian Virtue, OR as Something Legalistic
article
Randy's blog
I first became aware of tithing as a teenager when my pastor preached on the importance of supporting the local congregation. His sermon drew on Galatians 6:6: “Anyone who receives instruction in the word must share all good things with his instructor.”