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 the letter to the Hebrew is unknown.  The letter was written to a mostly Christian Jewish audience warning them of the dangers of reverting from their Christian beliefs to the non persecuted and allowed Jewish religion.

In our verses today the Hebrew Christians are warmed of the dangers of cultural Christianity – the Jews had historically failed to enter God’s rest because they did not trust or obey God’s word.  All of God’s revelation including that which came from his Son, Christ Jesus, is recorded in Scripture so the jews had God’s word but disregarded it.  The word of God is living and cannot be despised with impunity – – punishment for unbelief and obstinacy will be the fate of Hebrew Christians if they abandon their conversion to Christianity.

The gospel is life to believers and no creature is hidden from the eyes of God.  God, not man, is searching our hearts and souls and we should tremble at this for nothing is hidden from God.  Complete surrender to the word of God which imparts life to dead sinners is demanded in faith.  God’s word is active, effectual and accomplishes what God wills. It is not cultural nor relative.  God is the ultimate and authorative judge of thought and intention of the heart and mind – God knows the totality of the inner person.