There are several reasons why Balak would seem to be a true prophet of G-d. First Bil’am consistently says that he will only do what G-d says. When the messengers of Balak came to him, he says that he had to ask G-d for permission and when G-d told him no he did not go, 22:8-13. When the messengers of Balak returned, he said that if he received a house full of silver and gold he could only do what G-d would tell him, 22:18. On this occasion, G-d agreed to let him go, so Bil’am went but when he met Balak again he said he would only speak what G-d put into his mouth, 22:38. He continues to repeat this phrase to Balak, even as Balak gets angrier and angrier at him for blessing the Jewish people, 23:12,26; 24:12-14.
Second, the very fact that G-d would speak to Bil’am would seem to give him significance, as G-d does not speak to everybody. Bil’am could even call on G-d as he told the messengers of Balak that G-d would speak to him in the night, 22:8,19. However, in our discussion on 22:8-35, "The wizard of Petor," (http://www.lobashamayim.blogspot.co.il/2009/07/bemidbar-228-35-balak-wizard-of-petor.html) I argue that G-d did not really speak to Bil'am in 22:8-11,19,20 and that initially, Bil'am' s statements that he would only do what G-d said was part of his act to bargain for more money. If this is true, then these first two reasons are not indicative of any goodness on Bil'am's part.
Three, the blessings he gives are not only favorable to the Jewish people but also have been interpreted as signifying some of the most significant future events such as the coming of the Messiah (Bemidbar 24:17-19). The Talmud (Berakhot 12b, also Yerushalmi Berakhot) quotes R. Avihu son of Zutrti in the name of R. Yehuda the son of Zevida that Chazal wanted to include Bil'am's prophecies in the regular prayers but did not do so only because they were too long and would be a burden to the public. Afterwards, the blessing, mah tovu, 24:5, stated by Bil’am was included in the daily prayers. Furthermore, in the last blessings, the Torah records “that he knew the knowledge of the Most High” (24:16) which would be knowledge that only a prophet of G-d could know. The positive view of Bil’am appears in the Midrash (Numbers Rabbah, 14:20, and Sifrei Devarim 357) which compares Bil’am favorably in some ways to Moshe.
On the other hand, there are many reasons to think that Bil’am was really a scoundrel. First, the fact that he would ask G-d to curse the Jewish people shows that he cannot be a prophet since how could a prophet of G-d want to curse the people who made a covenant with G-d?
Second, as indicated in Numbers Rabbah 20:14, the story of the donkey, is a parody of Bil’am, as the Midrash records “this villain was going to curse an entire nation…yet he had to smite a donkey!” A donkey, an animal, was able to see a malakh of G-d while Bil’am this supposedly great prophet did not know what was going on, 22:22-31. Presumably, G-d would not create a miracle of a talking donkey and send a malakh to make fun of a true prophet of G-d.
Third, after Bil’am finished his blessings, the Jewish people sinned with the daughters of Moav, and 31:16 seems to imply that this sin was due to the words of Bil’am. Rashi (on 25:1) quotes from the Talmud (Sanhedrin 106a), that after Bil’am failed to curse the Jewish people, he told Moav that they should seduce the Jewish people to get them to sin so that G-d would be angry at the Jewish people. How could a prophet of G-d desire to cause the people to sin?
Fourth, 31:8 records that the Jewish people killed Bil’am but as noted by Rambam (on 22:31) the Jewish people would not kill a prophet of G-d.
Fifth, N. Leibowitz (1980, pp. 284, 286) notes that Bil’am did not act like other prophets. Prophets usually attempt to refrain from being prophets while Bil’am “hankers after prophecy… to force it down from Heaven through the medium of seven alters, seven bullocks, enchantments and solitude.” Also, she notes that prophets usually state in their prophecy "thus said G-d," while Bil’am said "thus said Bil’am," 24:3,15.
Accordingly, there are many reasons to think he was a prophet and many reasons to think he was a scoundrel, what is one to think of this Jekyll and Hyde?
The overwhelming traditional approach views Bil’am as a scoundrel. For example, in Pirkei Avot 5:22, Bil’am is portrayed as having an evil eye, a haughty spirit and a proud soul. Yet, then all the apparent positive aspects to Bil’am have to be explained.
How could Bil’am offer such great blessings/ prophecies if he was a scoundrel? Sanhedrin 105b quotes Rabbi Yohanon that Bil’am was forced to say the blessings under duress. According to this idea, Bil’am was not a prophet at all, and would have been like a zombie when he said the blessings. Yet, this explanation in the Talmud only refers to 23:5 where the text records that G-d put words into his mouth, while afterwards, by 24:2 Bil’am is referred to as a prophet.
Hirsch (on 22:8) suggests that Bil’am was both a prophet of G-d and a scoundrel. For some reason, Bil’am had a belief in monotheism which enabled him to become a prophet and thus G-d would speak to him, but he happened also to be an avaricious soul. I do not understand this idea since I assume that if a person is a prophet who can speak to G-d, then he would also be a morally upstanding person. Is a belief in monotheism enough to make a person a prophet?
Ramban (on 22:31) understands that Bil’am was a temporary prophet for the sake of the honor of the Jewish people to say the blessings. He became a prophet at the end of incident with the donkey, when the text records “that G-d opened the eyes of Bil’am,” 22:31, to enable him to see the malakh. The idea would be that he was so humiliated by the donkey that he realized the errors of his ways. However, after Bil’am finished the blessings he reverted back to being a sorcerer, and thus he could have advised the daughters of Moav to tempt the Jewish people.
I like this idea of the Ramban that Bil’am was transformed by the incident with donkey, but I am bothered how Bil’am could have reverted backwards so quickly. Hertz (1960, p. 681) explains “that there is nothing improbable in this heathen prophet, when his enthusiasm for Israel and righteousness had died away, sinking back to the old sorcerer.” To me this seems highly improbable.
After Bil'am realized that he could have been killed by the malakh, he admitted that he sinned (22:34), which sounds like a genuine repentant. We see that during the blessings he stopped with his sacrifices and disregarded his enchantment methods, 24:1.
Furthermore, the blessings he uttered, would likely have reinforced his transformation. I doubt that after all the incredible blessings, Bil'am would deliberately sin against G-d by teaching Moav how to incite the Jewish people to sin. After Balak yelled at Bil’am after the third blessing, Bil’am responded by predicting that Moav would be wiped out by the Jewish people, 24:17. This prediction is incongruent with the idea that at that same time he advised Moav to provoke the Jewish people to sin so that Moav could defeat the Jewish people.
Ramban (on 25:1) notes that the simple sense of the Torah is that Bil’am did not advise the women of Moav or Midyan to seduce the Jewish men since this fact is not mentioned in chapter 25. I believe that 31:16
should be understood to mean that after the people heard Bil'am's great blessings, they became euphoric, and this led them to chase after the women of Moav.
Why was Bil'am with Midyan (31:8) if he was not advising them to cause the Jewish people to sin? My geuss is that Midyan was the agent for arraigning Moav to hire Bil'am. The idea would be that Midyan had good relations with Bil'am, and hence either on the way home, 24:25, or some time after Bil'am returned home after stating the prophecies, he traveled to Midyan. Thus, he was with Midyan when the war with the Jewish people occurred.
Why was Bil'am killed if he did not advise Moav to sin with the Jewish people? Maybe, he was killed because he initially wanted to curse the Jewish people. Instead of the malakh killing Bil’am when he was riding the donkey the Jewish people killed him in the war with Midyan. His initial sin was so heinous that his repentance could not absolve him of punishment.
To return to the question of whether Bil'am was a saint or a sinner. My feeling is that initially Bil’am was a scoundrel, but he was transformed by the incident with the donkey to being a prophet temporarily. Afterwards, he did not revert to being a scoundrel since he did not advise Midyan or Moav to sin with the Jewish people. Yet, he also did not remain a prophet, but he became an ordinary person. This second change occurred already by the forth blessings when he was a big talker that he claimed that "he knew the knowledge of the Most High,", see our discussion on 24:14-25, "The fourth blessing" (http://www.lobashamayim.blogspot.co.il/2010/06/bemidbar-2414-25-balak-fourth-blessing.html)
The idea is that after going from one extreme to the other, Bil'am ended up in the middle. (This idea is similar, though in a different context, to the Rambam's idea that by temporarily adopting extreme character traits one is led to the mean character traits, see his Laws of opinions 2:2, and Shemonah Perakim.) Once, Bil'am was no longer a prophet, then he was killed for his initial sin.