Much has already been written about the war against Hamas in Gaza, but very few have asked the question: What can we learn from our sources about the current conflict? During the past eight years, Palestinian terrorists have fired many thousands of rockets at civilian targets. More specifically, since we withdrew from Gaza in August 2005 - to allow the Palestinians to govern themselves - terrorists fired more than 6,000 rockets and mortars at civilian targets. Finally, on December 27, after many explicit warnings, the State of Israel decided to react by bombing launch sites, terrorist bases, homes of Hamas leaders and some 600 tunnels which have been used to smuggle weapons and rockets. It then sent in ground troops. The moral situation is extremely complex because the Hamas terrorists purposely hide behind civilians, in mosques, schools and even hospitals. It is difficult for our soldiers, officers and leaders to know what to do. Our sages taught us in Pirkei Avot (5:22): "Turn it and turn it again for everything is in it." That is why, in times of trouble, Jews have traditionally gone "back to the sources" to find comfort and guidance. The sources below attempt to do just that. Self-defense According to rabbinic law, there is no doubt that it is permissible to kill terrorists in self-defense, for the following three reasons: The Torah rules that if a "thief is discovered tunneling [into a house for housebreaking] and is beaten and dies, there is no bloodguilt in his case" (Exodus 22:1). Rava explained that the thief assumes that the homeowner is going to defend his property and he, in turn, will be willing to kill the homeowner. Therefore, the Torah is telling us: "If somebody comes to kill you, kill him first" (Sanhedrin 72a). In other words, if someone tunnels into an individual's home to steal, and even more so if he intends to kill that person, that person should kill the attacker as an act of self-defense. It is worth noting that the Torah gives the example of tunneling, one of the standard activities of the Hamas terrorists. Furthermore, a group of Jews is allowed to defend itself against attackers, even on Shabbat. This was first determined by Mattathias and the Maccabees, after the Greeks killed 1,000 Jews on Shabbat because they would not defend themselves (I Maccabees 2:29-41). The Talmud ruled (Eruvin 45a) that if a group of non-Jews besieged Jewish towns on Shabbat to kill Jews, the Jews go out in their armor and desecrate Shabbat. Furthermore, in a border town, the Jews go out in their armor and desecrate Shabbat even if the non-Jews only came to rob the town. And so ruled Maimonides (Laws of Shabbat 2:23) and the Shulhan Aruch (Orah Haim 329:6-7). The Rema adds (ibid.): "And even if they have not yet come but only want to come." In other words, in a border town, a preemptive strike against the enemy is permissible on Shabbat even to protect property; how much the more so to protect lives on a weekday. Finally, two sources go much further. They state that a war of self-defense is not only permitted but rather required. Midrash Shmuel determines (22:2, ed. Buber, p. 110) that David's war against the Philistines - which was self-defense - was a mitzva, a commanded war, or a hova, an obligation. Moreover, Maimonides ruled (Laws of Kings 5:1) "which war is a commanded war?... to help Israel against an enemy who attacks them." Attitude toward POWs and noncombatants On the other hand, there are sources which warn us not to harm prisoners or noncombatants. The Bible relates (II Kings 6:21-23) that the prophet Elisha asked God to temporarily blind the troops of Aram, and he then led the troops to Samaria. The king of Israel asked Elisha: "Shall I strike them down?" Elisha's reply is not entirely clear, but according to Rabbi Levi ben Gershom (ad loc.), he replied: "Would you strike down with your sword and bow people whom you captured?!" Similarly, Philo of Alexandria stated in the first century C.E. that Jews do not kill non-combatants (The Special Laws 4:224-225): The Jewish nation, when it takes up arms, distinguishes between those whose life is one of hostility and the reverse. For to breathe slaughter against all, even those who have done little or nothing amiss, shows what I would call a savage and brutal soul. When I was a reservist in the IDF, I used to guard Palestinian prisoners. I therefore know from firsthand experience that Palestinian prisoners are treated well. Indeed, the prisoners had better living conditions than the reservists who were guarding them, including couches, TVs, stoves and more. As for noncombatants, that is obviously a major challenge in Gaza, which is densely populated and where the terrorists use civilians as human shields as standard procedure. Nonetheless, the IDF takes great efforts not to harm civilians. There are legal advisers at command centers to ensure compliance with the laws of war; Israel has repeatedly warned civilians of impending attacks even though it has then lost the element of surprise; it has taken the unprecedented step of applying a unilateral cease-fire every day for three hours to allow hundreds of trucks of food and medical supplies into Gaza. Two words of warning before every battle We must teach our soldiers to remember two sources when they go out to fight our enemies: When Jacob heard that Esau was coming, it says: "And Jacob was greatly frightened and distressed" (Genesis 32:8) and the midrash explains: "frightened - lest he be killed; and distressed - lest he kill" (Genesis Rabba 76:2). When Israel left Egypt "the angels wanted to sing. Said God: "My handiwork [the Egyptians] are drowning in the sea - and you are singing?!" (Megila 10b). A Jew must share in the distress of the community We have learned in Ta'anit fol. 11a: Our rabbis have taught: When the community is in trouble, let not a man say "I will go to my house, and I will eat and drink and all will be well with me"... But rather a man should share in the distress of the community... He who shares in the distress of the community will merit to behold its consolation. The message of this passage is clear: When the Jews of Israel are in trouble, Diaspora Jews must share in their distress by taking part in solidarity missions and demonstrations and by donating tzedaka to help them. Some cynics say that missions and demonstrations are a waste of time; they are not. They give encouragement to the Jews of Israel who are constantly criticized by the United Nations and many countries. Similarly, during the past few weeks, tens of thousands of Israelis have donated food and toys to communities near Gaza and hosted families and children who sought respite from the rocket attacks. This is at it should be. Jews must share in the distress of the community. Israel and the nations of the world In the book of Esther (3:9), Haman says to Ahashuerus: "If it please the king, let it be written that they be destroyed." The midrash (Esther Rabba 7:13) adds: "Ahashuerus replied: 'You cannot prevail against them, since their God will not entirely forsake them. See what He did to the kings who preceded us and who laid hands upon themâ€¦ Whoever comes against them to destroy themâ€¦ is wiped out.'" When Haman persisted, Ahashuerus said to him: "Since you are so insistent, let us consult the wise men and the magicians." He thereupon convened all the wise men of the nations and asked them: "Is it your desire that we destroy this nation?" They replied that it is too dangerous because God protects His children, the people of Israel; look what happened to Pharaoh and Sennacherib. Haman then told them that God is now old and cannot do anything, since Nebuchadnezzar has already gone up and destroyed His house and burned His temple and exiled Israel and scattered them among the nations. They then came around to his opinion and agreed to destroy Israel, and they wrote letters and signed them. "There is nothing new under the sun" (Kohelet 1:9). This medieval midrash could have been written yesterday. All we need to do is substitute Ismail Haniyeh or Mahmoud Ahmadinejad for Haman and the UN for "all the wise men of the nations." It should be noted that "the wise men of the nations" do not tell Ahashuerus not to destroy the Jews because it is immoral, only because it is too dangerous. When Haman tells them that the Jewish God is now weak and unable to protect the Jews, they immediately agree to kill all of the Jews. The UN as a body does not want to destroy the State of Israel, but there is no question that many of its members want to harm the State of Israel if they think they can get away with it. Despite it all Yosef Haim Brenner (1881-1921) was a leading Labor Zionist and Hebrew author. He wrote the following passage in 1917: Our youth throughout the world must now know the truth about the Land of Israel. They should know that the place is not a bed of roses, that the land is poor, hardly magical... Wages are low, food is scarce and expensive, the needs are greater than our capacity; lofty spirituality can be found at every corner, and on top of that, malaria eats up body and soul... All of this should be known in the Jewish Diaspora, and should give birth to a sentiment of despite it all in the hearts of our youth!... And only that pioneer whose "despite it all" becomes part of his very being, only that pioneer who is ready for everything - and not only in words, only he should be allowed to come. He and no one else. Despite it all has been the motto of the State of Israel since it was founded. Arab armies and terrorists have been trying to destroy us since 1948 and yet we have built a vibrant Jewish state which is the only democracy in the Middle East. We shall persevere despite it all because "the guardian of Israel neither slumbers nor sleeps" (Psalms 121:4). Am Yisrael hai! The writer is the president of the Schechter Institute of Jewish Studies in Jerusalem.