According to v. 4, this sermon is intended to dispel our fears.  Verses 1-2 describe the cause of fear–powerful ruling forces.  Verses 3-9 function as a call to faith.  Verses 10-23 tell the results of unbelief.  The object of our faith is in v. 14, “Immanuel.”  This sign from God to Ahaz gives Believers the opportunity to be “firm in faith” (v. 9).  This faith keeps us from making the kind of fear-induced, bad decisions that Ahaz made–to trust Assyria instead of God.  One way to preach the Gospel in Isaiah 7 is to highlight our Lord’s ability to “refuse the evil and choose the good,” something no other Israelite had done or could do.  His perfect life allowed Him to make a perfect sacrifice as a crown of thorns was put on His head on the Cross (cf. vv. 23-25).