The word of God.  Sharp as a two-edge sword.  The living word of the Almighty Father through His son Jesus Christ and in the power of the Holy Spirit.  The Word is not only "alive" but is powerful and as such "acts". The words "Let there be light" called into being light. The Word, through the prophet Isaiah for example, has also made some astounding promises, among them, that His word would not return to Him unfulfilled without first carrying out His good pleasure and having achieved what it was sent to do (Is 55:11). All the more reason, therefore, for us to read and ponder His Word with expectant faith and great confidence.