Numbers 22:31

Opened the eyes of Balaam] Up to this point Balaam has been like a blind man. He has been determined to have his own way. But now he sees it is useless trying to deceive God or fight against Him. Like Saul he finds it is 'hard to kick against the pricks': cp. Acts 9:4. The refusal of his erstwhile docile ass to carry him further is the God-employed means of bringing the obstinate prophet to his senses. How this was done it is vain to speculate. Some explain away the incident of the vision and the ass speaking e.g. as a dream which Balaam had before starting, or a vivid impression made upon him by the liveliness of his own thoughts; but evidently the writer of the narrative believed in the reality of both. In this he simply occupies the standpoint of his age.