[We must deal] with the general scope and
implication of the statement that “the Eternal One of Israel does not lie and
does not repent, because he is not a man to repent” (1 Sam 15:29). The statement
here is very similar to the one in Num 23:19, where it is said, “El is not a
man (‘ȋš) that he should dissemble (wikazzeb) or a human being (ben-‘ādām) that he should repent (wěyitneḥām).” The accompanying line (v
19b) shows that what is meant by the statement concerns God’s reliability and
consistency, “Shall he say something and not do it/or speak and not establish
it?” The conclusion would be in both places that God is different from man in
that he is faithful and just; he does what he says he will do. He does not say
one thing and do another, neither does he change his mind for frivolous reasons
or no reason. He is not capricious or arbitrary but is truthful, consistent,
and reliable. In that sense he does not repent: he does not change his mind and
then change it again without cause. (Francis I. Andersen and David Noel
Freedman, Amos: A New Translation with
Introduction and Commentary [AB 24A; New York: Doubleday, 1989], 653)