# takes away the disgrace from Israel

"stops him from disgracing Israel" 

# Who is this uncircumcised Philistine that he should defy the armies of the living God?

"This uncircumcised Philistine certainly has no power that he should defy the armies of the living God!" 

# this uncircumcised Philistine

This is an insult and indicates that Goliath does not belong to the living God. The people of Israel often used the term "uncircumcised" to refer to Gentiles. Here it is used to describe the Philistines.