And David spake to the men that stood by him, saying, What shall be done to the man that killeth this Philistine, and taketh away the reproach from Israel? for who is this uncircumcised Philistine, that he should defy the armies of the living God? (1 Samuel 17:26)

Take away the reproach! Among all the other things that were demonstrated and accomplished when David slew the Philistine, Goliath, this was quite significant. 

Israel was covering in the face of pagans. Goliath was taunting the armies of Israel and by extension the God of the armies of Israel. The people and God Himself was being reproached and David was not going to have it. His victory caused the Philistine army to flee and the name of the Lord was magnified. 

Likewise the reproach of man, brought on by sin, has fallen upon Christ who bore their sin. But alas, upon slaying the devil the reproach of believers has been taken away from them…and the name of the Lord is magnified.

– brother Pat Woods