"How goodly are thy tents o' Ya'acov, thy tabernacles o' Israel" (Numbers 24:5). This well known verse that appears at the beginning of the prayer book is the verse said by Bilam the wicked, the enemy of Israel.

If this is the case, why have Bilam's words received such a prominent place in the siddur?

There is the famous joke about the Jew who read an anti-Semitic newspaper every morning.

Once his friend Shmulik met him and asked him: "Tell me Yankel…aren't there enough jewish newspapers that you are reading an anti-Semitic one?

He said to Shmulik , "Look…I read in the Jewish newspaper about the number of Israelis living under the poverty line, about how we dare not move a finger without the authorization of the United States and about the fact that soon there will be more Arabs than Jews living in the State of Israel. Then I open an anti-Semitic newspaper and I read that there are tens of millions of Jews in the world, that we dictate the policy in Iraq to the United States and that all Jews are millionaires…you tell me: Which newspaper would you rather read??"
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There is a large gap between the image that a person or a people have of himself and the image of a person or a people in the eyes of the world.

I do not know how many Jews would be willing to say "How goodly are thy tents o' Ya'acov, thy tabernacles o' Israel".

If this is so, then why Bilam's words received such a special place in the siddur?

Rabbi Acha said in the name of Rabbi Haninah: It would have been more worthy to put the reproaches in the mouth of Bilam and the blessings in the mouth of Moshe. But if Bilam had reproached them, then Israel would say, it is our enemy who reproves us, and if Moshe had blessed them, then the world would say one who loves them has blessed them. The Holy One said: Moshe who loves them will reproach them and Bilam who hates them will bless them, thus Israel will demonstrate the validity of the blessings and the reproaches.

There is no value to the reproach of an enemy. Of course that there is a very important value to the blessing of one who loves us (A parent's or a Rabbi's blessing, by example), but the very fact that it is the enemy who gives the blessing, grants the blessing legitimacy.

Everyone knows that in the natural course of events, enemies tend to curse and friends are wont to bless. But when an expression of benevolence is uttered by an enemy, it has a completely different meaning.

The blessing of an enemy is a true blessing.