For the word of God is living and powerful and sharper than any two edged sword, piercing even to the division of soul and spirit, and of joints and marrow, and is a discerner of the thoughts and intents of the heart.  (13) And there is no creature hidden from His sight, but all things are naked and open to the eyes of Him to whom we must give account.

The author of Hebrews is unknown but the audience seemed to be Jewish Christians who were in danger of renouncing Christ as Messiah in face of increasing prosecution.  This letter begins by telling the reader that God had revealed His word in various times and in various ways – and now fully through His Son – who the author makes clear is fully divine and fully human, having suffered and died having accomplished redemption for lost sinners.  His Word is the message of salvation.

The cautionary example we are given is the Israelites who rebelled with unbelief in the desert after having been led out of Egypt.  They were not allowed to enter God’s rest – they were not faithful.  The danger of unbelief and rebellion exists today and the warnings continue – we too have the good news proclaimed to us.  The Israelites didn’t have the gospel – the word of the completion of Christ’s work of redemption and the doctrine that Christ continues to intercede for us as our High Priest.  The author is telling us we must make every effort to enter into God’s rest/our salvation.

In verse 11 readers are told to make every effort to enter that rest so that no one may fall by following the same pattern of disobedience.  If a whole generation of Israelites failed to enter Gods rest after all the signs and wonders they experienced we are certainly in danger of doing this too. In verse 12 the author is saying to pay attention to the Word of God ( the Bible).  The Word of God is active and will do all the work – we need to believe it and our actions will come from our belief.  The Word of God exposes the thoughts of our hearts – it judges our thoughts and intentions.

God has provided a salvation for us that we cannot attain on our own.  The author of Hebrews is telling us that the Word of God reveals God to us and also we are revealed before God – he has seen into the hearts of the wavering Jewish Christians who are thinking of rejecting Jesus for personal safety.  But God knows everything and this doubt and these intentions will need to be answered for.  Our spiritual condition is exposed to God always and completely.