Charles Ellicott Commentary Numbers 24:23

"And he took up his parable, and said, Alas, who shall live when God doeth this?" — Numbers 24:23 (ASV)

When God does this.— These words may be rendered, since (or, from the time that) God sets (or, determines) it (or, this)— quando faciet ista Deus (Vulgate); or, because God determines it (or, this).