This psalm consists of a prayer for help- 64:1-2- A description of the enemy- 64:3-6- and a dramatic intervention by God- 64:7-10.

Key words:
hide- 64:2, 4 compare vs. 2 with  II Kings 11:2; II Chron. 22:11. 
tongue- 64:3, 8
arrow- 64:3, 7
shoot- 64:4, 7
blameless- 64:4, 6
suddenly- 64:4, 7
see- 64:5, 8
fear- 64:4, 9

Also listen for how Jesus fulfills the Psalm.