Ten degrees - literally, "ten steps." It is not, perhaps, altogether certain whether the "dial of Ahaz" 2 Kings 20:11 was really a dial with a gnomon in the center, and "degrees" marked round it, or a construction fur marking time by means of "steps." Sundials proper had been invented by the Babylonians before the time of Herodotus; but the instrument here was probably an instrument consisting of a set of steps, or stairs, with an obelisk at the top, the shadow of which descended or ascended the steps according as the sun rose higher in the heavens or declined.

The question as to the mode whereby the return of the shadow was produced is one on which many opinions have been held. Recently, it has been urged that the true cause of the phenomenon was a solar eclipse, in which the moon obscured the entire upper limb of the sun; and it has been clearly shown that if such an occurrence took place a little before mid-day, it would have had the effect described as having taken place - i. e., during the obscuration of the sun's upper limb shadows would be sensibly lengthened, and that of the obelisk would descend the stairs; as the obscuration passed off the reverse would take place, shadows would shorten, and that of the obelisk would once more retire up the steps. If this be the true account, the miracle would consist in Isaiah's supernatural foreknowledge of an event which the astronomy of the age was quite incapable of predicting, and in the providential guidance of Hezekiah's will, so that he chose the "sign" which in the natural course of things was about to be manifested.

And Isaiah said, this sign shalt thou have of the Lord, that the Lord will do the thing that he hath spoken,.... Cure him of his disorder, so that he should be able to go to the temple on the third day:

shall the shadow go forward ten degrees, or go back ten degrees? that is, the shadow of the sun on a dial plate; it was left to his option to choose which he would, as the confirming sign of his recovery.

הצּל הלך: "the shadow is gone ten degrees, if it should go back ten degrees?" The rendering, visne umbram solarii decem gradibus progredi an ... regredi, which Maurer still gives after the Vulgate, vis an ut ascendat ... an ut revertatur, cannot be grammatically reconciled with the perfect הלך, and is merely a conjecture founded upon the answer of Hezekiah.

(Note: Hitzig and Knobel would therefore read הלך, though without furnishing any proofs that the inf. abs. is used for the future in the first clause of a double question, especially if the ה interrog. is wanting, and there is no special emphasis upon the verbal idea.)

According to this answer, "it is easy for the shadow to decline (i.e., to go farther down) ten degrees; no (sc., that shall not be a sign to me), but if the shadow turn ten degrees backwards," Isaiah seems to have given the king a choice as to the sign, namely, whether the shadow should go ten degrees forward or backward. But this does not necessarily follow from the words quoted. Hezekiah may have understood the prophet's words וגו הצּל הלך hypothetically: "has the shadow gone (advanced) ten degrees, whether it should," etc.; and may have replied, the advance of the shadow would not be a sure sign to him, but only its going back.

And Isaiah said, This sign shalt thou have of the LORD, that the LORD will do the thing that he hath spoken: shall the shadow go forward ten degrees, or go back ten degrees?

20:1-11 Hezekiah was sick unto death, in the same year in which the king of Assyria besieged Jerusalem. A warning to prepare for death was brought to Hezekiah by Isaiah. Prayer is one of the best preparations for death, because by it we fetch in strength and grace from God, to enable us to finish well. He wept sorely: some gather from hence that he was unwilling to die; it is in the nature of man to dread the separation of soul and body. There was also something peculiar in Hezekiah's case; he was now in the midst of his usefulness. Let Hezekiah's prayer, see Isa 38. interpret his tears; in that is nothing which is like his having been under that fear of death, which has bondage or torment. Hezekiah's piety made his sick-bed easy. O Lord, remember now; he does not speak as if God needed to be put in mind of any thing by us; nor, as if the reward might be demanded as due; it is Christ's righteousness only that is the purchase of mercy and grace. Hezekiah does not pray, Lord, spare me; but, Lord, remember me; whether I live or die, let me be thine. God always hears the prayers of the broken in heart, and will give health, length of days, and temporal deliverances, as much and as long as is truly good for them. Means were to be used for Hezekiah's recovery; yet, considering to what a height the disease was come, and how suddenly it was checked, the cure was miraculous. It is our duty, when sick, to use such means as are proper to help nature, else we do not trust God, but tempt him. For the confirmation of his faith, the shadow of the sun was carried back, and the light was continued longer than usual, in a miraculous manner. This work of wonder shows the power of God in heaven as well as on earth, the great notice he takes of prayer, and the great favour he bears to his chosen.