Exodus 4:18

Moses returned to Jethro Justice and decency required Moses to acquaint his father-in-law with his intention of going into Egypt; but he thought fit to conceal from him the errand upon which God sent him, lest he should endeavour to hinder or discourage him from so difficult and dangerous an enterprise. So that Moses, in this instance, has given us a rare example of piety and prudence, in that he took care to avoid all occasions and temptations to disobedience to the divine commands; as well as of singular modesty and humility, in that such glorious and familiar converse with God, and the high commission with which he had honoured him, neither made him forget the duty he owed to his father-in-law, nor break out into any vain-glorious ostentation of such a privilege.