30 Heb “he answered and said.” The referent (Balaam) has been specified in the translation for clarity.
31 The verb שָׁמַר (shamar) means “to guard, watch, observe” and so here with a sense of “be careful” or even “take heed” (so , ). The nuance of the imperfect tense would be obligatory: “I must be careful”—to do what? to speak what the Lord has put in my mouth. The infinitive construct “to speak” is therefore serving as the direct object of שָׁמַר.
32 The clause is a noun clause serving as the direct object of “to speak.” It begins with the sign of the accusative, and then the relative pronoun that indicates the whole clause is the accusative.

In other versions

And he answered and said, “Must I not take care to speak what the Lord puts in my mouth?”

He answered, “Must I not speak what the Lord puts in my mouth?”

He answered, “Shouldn’t I say exactly what the Lord puts in my mouth?”

But Balaam replied, “I will speak only the message that the Lord puts in my mouth.”

He answered and said, “Should I not speak what Yahweh puts in my mouth?”

And he answered and said, Must I not take heed to speak that which the Lord hath put in my mouth?

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