Hebrews 12:28 -
 
Chapter 12, wanted to do outline on whole thing, it goes together.
 
Background: writer is painting loving picture of God. Contrasting with the fear Israel had at Mt. Sinai with the grace we have approaching Mt. Zion. Different picture here in 25-29 than in preceding verses.
 
V25 warning to not refuse the Lord, referring to 3:16-19, where Israelites cannot enter promised land because of unbelief.
 
V26 another reference to the voice of the Lord shaking things  
Reference to Haggai 2:6-9 about shaking the earth
 
V27 explains the promise from Haggai
 
The picture being painted is that the things that will remain are the things of Christ.
 
V28 assurance part, with command to show grace/gratitude. Grace in what? A call to have grace permeate our lives in general, not one specific area.
 
Serve: acceptably, reverence, godly fear - a constant carefulness
 
V29 not to believers, but God's attitude to those who are against him. Should inspire our attitude of grace when we consider how gracious God is to us, considering how fearful He should be to all who resist Him.