And Moses called to all Israel and said to them, You have seen all that Jehovah did before your eyes in the land of Egypt to Pharaoh and to all his servants, and to all his land. Your eyes have seen the great trials, the signs, and those great miracles. Yet Jehovah has not given you a heart to perceive, and eyes to see, and ears to hear, until today. (Deuteronomy 29:2-4)

Deu 29:4 - Yet the Lord - That is, you have perceived and seen them with the eyes of your body, but not with your minds and hearts; you have not yet learned rightly to understand the word and works of God, so as to know them for your good, and to make a right use of them, and to comply with them: which he expresseth thus, the Lord hath not given you, &c. not to excuse their wickedness, but to direct them to whom they must have recourse for a good understanding of God's works; and to intimate that although the hearing ear, and the seeing eye, be the workmanship of God, yet their want of his grace was their own fault, and the just punishment of their former sins; their present case being like theirs in Isaiah's time, who first shut their own eyes and ears that they might not see and hear, and would not understand, and then by the righteous judgment of God, had their eyes and ears closed that they should not see and hear, and understand. God's readiness to do us good in other things, is a plain evidence, that if we have not grace, that best of gifts, 'tis our own fault and not his: he would have gathered us, and we would not.  (John Wesley's Explanatory Notes)