Jamieson, Fausset and Brown on Genesis 32:4

4. Thus shall ye speak unto my lord Esau--The purport of the message was that, after a residence of twenty years in Mesopotamia, he was now returning to his native land, that he did not need any thing, for he had abundance of pastoral wealth, but that he could not pass without notifying his arrival to his brother and paying the homage of his respectful obeisance. Acts of civility tend to disarm opposition and soften hatred (Ec 10:4).

Thy servant Jacob--He had been made lord over his brethren (compare Ge 27:29). But it is probable he thought this referred to a spiritual superiority; or if to temporal, that it was to be realized only to his posterity. At all events, leaving it to God to fulfil that purpose, he deemed it prudent to assume the most kind and respectful bearing.