It's the "Lord's Day," not the "Lord's Morning"

How do you think about using your Sundays?

Mark Dever said on the Albert Mohler program:

Biblically, we don’t have to have the whole day. But I want to take the spirit of the fourth commandment and use that in a Christian’s life to say, “Look, give this to the Lord and his work as you tithe your money, so tithe your time. Let this be the tithe of your time. So in our congregation, we require the Sunday Morning and ask them to be there on Sunday night. Don’t use Sunday as a second Saturday. We don’t want it to be convenient in that sense. We want it to interrupt your life to make you think about the six days that are coming up… The Puritan’s called it “the market day of the soul.”