Balak certainly takes very seriously Bilaam’s power to bless or curse. And the Torah seems to acknowledge this power; after all, it was very important to HaShem to dramatically change Bilaam's curses to blessings.
However, not only prophets, whether righteous ones like the prophets of Israel or wicked ones like Bilaam, have the power of blessing and curse. Our Sages tell us that ordinary people also have this power: “Never make light of the blessing of an ordinary person”; “Don’t make light of the curse of an ordinary person” (Megilla 15a).
Of course our power to bless and curse is not some magical force but merely a consequence of the fact that HaShem hears and considers our prayers and requests. This is part of His continuing concern and involvement with human experience. “Don’t oppress any widow or orphan. If you should oppress them, and they should cry to Me, I will surely hear their cry” (Shemot 22:21-22.)
However, this is a power that needs to be used very carefully indeed. “Rav Chanan said, anyone who submits his fellow’s judgment [to the Heavenly Court], he is punished first... This applies as long as he has access to earthly [human] justice.
Rebbe Yitzchak said, woe to the crier even more than to the one he cries about” (Bava Kamma 93a).
This consideration is so compelling that we find that even the most righteous of the holy Tannaim refrained from praying for judgment against the very wicked of Israel (See Berakhot 10a, Megilla 28a, Gittin 7a).
The Rema turns this insight into a ruling: “It is forbidden to request Heavenly judgment on someone who has done us wrong – assuming there is access to earthly justice. And anyone who cries out on his fellow, he is punished first. And there are those who say that even if there is no access to earthly justice, it is forbidden to cry unless the wrongdoer is notified first” (Choshen Mishpat 422:1).
We might think that the problem here is vindictiveness. Unnecessarily invoking Divine judgment seems to show a desire for revenge, rather than justice. The commensurate response is to punish the wronged individual.
However, Rashi gives a different explanation. The gemara in Berakhot states, “Three things call attention to a person’s sins. They are: a collapsing wall, assuming prayers will be fulfilled, and invoking Heavenly judgment on one’s fellow man” (Berakhot 55a). Rashi explains that as a result of these, “They begin on high to carefully examine his acts, saying, This person seems very confident of his merits; let’s see what they are” (See also Divrei Shalom).
In other words, this principle is not a deviation from the principles of strict justice but rather a fulfillment of it. HaShem listens to the cry of the wronged individual, and He carefully considers the petitions on its merits. At the same time, “Heaven doesn’t grant halves” (Yoma 69b). If HaShem agrees to sit in judgment, then it is only fair that the petitioner too be subject to scrutiny.
The phenomenon of prayer, of the Almighty listening and weighing the desires of each individual human who turns to Him, is a mighty testimony to the greatness of man. It is not pre- sumptuous to ask G-d for our needs; on the contrary, He wants us to view Him as father and king.
Endangering ourselves, as in the case of the crumbling wall, is altogether different; it shows that we are sure we are worthy of being answered. This surely invites Divine scrutiny, and we find only isolated instances of righteous people who relied on miraculous intervention.
And asking HaShem for judgment is an entirely different level. Not only does the petitioner think he is worthy; he is sure he is even worthier than the one who has wronged him! Since we can never completely know the circumstances of another individual, even the most righteous are forbidden to request Divine judgment in such cases unless it is absolutely a last resort.