Numbers 22:18

מלא ביתו כסף וזהב [IF BALAK WOULD GIVE ME HIS HOUSE] FULL OF SILVER AND GOLD — This tells us that he was avaricious and covetous of other peoples wealth. He said: He ought to give me all his silver and gold, for, behold, he would otherwise have to hire many armies to fight against them. Even then it is doubtful whether he would conquer or not conquer, but “I” would certainly conquer (Midrash Tanchuma, Balak 6). לא אוכל לעבר I CANNOT GO BEYOND [THE WORD OF THE LORD] — Against his own will he divulged to them that he was under the control of others, and he prophesied here that he would be unable to annul those blessings with which the patriarchs had been blessed by the mouth of God (Midrash Tanchuma, Balak 6).

And Bil῾am answered and said to the servants of Balaq, If Balaq would give me his house full of silver and gold, I cannot go beyond the word of the Lord my God, to do less or more.

וַיַּ֣עַן בִּלְעָ֗ם וַיֹּ֙אמֶר֙ אֶל־עַבְדֵ֣י בָלָ֔ק אִם־יִתֶּן־לִ֥י בָלָ֛ק מְלֹ֥א בֵית֖וֹ כֶּ֣סֶף וְזָהָ֑ב לֹ֣א אוּכַ֗ל לַעֲבֹר֙ אֶת־פִּי֙ יְהֹוָ֣ה אֱלֹהָ֔י לַעֲשׂ֥וֹת קְטַנָּ֖ה א֥וֹ גְדוֹלָֽה׃