Ninja vs Spartan

Being outnumbered 2 to 1 by males at home, I sometimes watch programs that are not on Lifetime or HGTV. The guys were watching a program that was scientifically trying to determine if an expert Ninja warrior battled a Spartan soldier who would win. Not being very familiar with either fighting style, and noticing that the program wasn't particulary bloody I watched with fascination.
The Spartan carried a large round shield and a spear, and the Ninja carried a chain with a metal ball on one end and a scythe kind of blade on the other. What fascinated me the most was the Spartan's powerful use of his shield. The scientific data listed the impact velocity of the shield on his opponent to be greater than an explosion or head on collision. I put my money on the Spartan. I had never read about using the shield as an offensive weapon.

Shield picture and purchasing info can be found at ApexRG

Of course my mind went to the Ephesians 6 scriptures on the armor of God. I had often heard that the "sword of the Spirit, which is the Word of God" was the only offensive weapon. Now I'm wondering if the Romans used their shields the same way as the Spartans - to bash, to pound, even almost guillotine their opponents.
So, if the shield of spiritual armor is faith, how can I use it offensively? Like the ancient warrior, I must exercise faith that opposes the enemy, halts him, cuts off his head, and defeats his plans. Faith that is bold, agressive, and decisive will win the day.
Want to know who won? The Spartan! He was given a 65% projection to defeat the Ninja. At the end of the program, the narrator concluded:
The Ninja could injure and make the Spartan bloody, but the Spartan could kill the Ninja!
Take up your shields of faith, mighty army! This is a good day for war.