'Uncircumcised' in the Bible

Jonathan said to his young armor bearer, “Come, let us cross over to the garrison of these uncircumcised men; it may be that the Lord will work for us. For there is nothing to prevent the Lord from saving, whether by many or by few.”

Then David spoke to the men who were standing by him, “What will be done for the man who kills this Philistine and removes the disgrace [of his taunting] from Israel? For who is this uncircumcised Philistine that he has taunted and defied the armies of the living God?”

Your servant has killed both the lion and the bear; and this uncircumcised Philistine will be like one of them, since he has taunted and defied the armies of the living God.”

Saul said to his armor bearer, “Draw your sword and pierce me through with it, otherwise these uncircumcised [Philistines] will come and pierce me through and abuse and mock me.” But his armor bearer would not, because he was terrified [of doing such a thing]. So Saul took his sword and fell on it.