NOTES for Isa 55:1-13
Prophetic speech often seems spontaneous and therefore chaotic, yet attentive reading can reveal an orderly, though unfamiliar, logical sequence. It may escape us, because we are inclined to perceive not only the Word of God, which uses human speech, but even the Lord Himself in accordance with our habitual ideas. And the conviction that everything must be paid for, and that there is no such thing as a free lunch, has become firmly ingrained in our thinking... Thus we ourselves reject the possibility of receiving the many gifts that God gives entirely without payment.
It is no accident that precisely here, after revealing through the prophet that He gives His mercies generously and freely, without money and without price, the Lord says that His thoughts and ways cannot be compared with human ones. At first such words may evoke a sense of an impassable abyss, and there is great truth in that feeling. But an abyss that is insurmountable from our side is no obstacle to the Lord: His mercy crosses it without difficulty.