Midrash su I Samuele 26:8

"The Philistines came upon Israel relying upon the strength of Goliath." What does Goliath mean? Said R. Jochanan: "Who stood with defiance before the Lord, as it is said (I Sam. 26, 8) Select for yourselves one man, and let him come down to me. And the word Ish (man), refers to none else than the Lord, as it is said (Ex. 15, 3) The Eternal is the Lord (Ish) of war. The Holy One, praised be He, then said: "I shall therefore cause him to fall into the hands of one who is the son of a man called Ish" as it is said (I Sam. 17, 12) Now David was the son of that Ephrathite, (Ish Ephrathi). R. Jochanan in the name of R. Maier said: "In three places was that wicked caught, through the explanation of his own mouth. Once, when he said (Ib., ib. 8) Select for yourselves one man, and let him come down to me. At the second time when he said (Ib., ib. 9) If he be able to fight with me, and he kills me, then will we be unto you as servants. And at the third time when he said (Ib., ib. 43) Am I a dog, that thou comest unto me with sticks?" But was not the same expression also used by David when he said, (Ib.,ib.45) Thou comest unto me with a sword, and with a spear, and with a javelin. This David merely used it as a reply, he said to him: But I come to thee in the name of the Lord of hosts, the God of the Arrays of Israel, that thou hast defied. (Ib., ib. 16) And the Philistines drew near, morning and evening. Said R. Jochanan: "He picked out that time purposely, so that he should cause Israel to neglect the reading of S'hma in the morning and the evening." (Ib., ib., ib.) And presented himself forty days. These forty days correspond to the forty which were postponed in accepting the Torah (Ib., ib. 4) And there went out the champion (habenayim) out of the camp of the Philistines. What does benayim mean? Said Rab: "This means that he was clean of the least blemish;" Samuel said: "This means that he was the middle aged of his brothers." In the academy of R. Shila, it was taught: Benayim means that he was built like a building.