And Isaiah the prophet cried unto the LORD: and he brought the shadow ten degrees backward, by which it had gone down in the dial of Ahaz.

And Isaias the prophet called upon the Lord, and he brought the shadow ten degrees backwards by the lines, by which it had already gone down in the dial of Achaz.

And Isaiah the prophet cried to Jehovah, and he brought the shadow back on the degrees by which it had gone down on the dial of Ahaz, ten degrees backward.

And Isaiah the prophet calleth unto Jehovah, and He bringeth back the shadow by the degrees that it had gone down in the degrees of Ahaz, backward ten degrees.

Then Isaiah the prophet made prayer to the Lord, and he made the shade go back ten degrees from its position on the steps of Ahaz.

And so the prophet Isaiah called upon the Lord. And he led back the shadow, along the lines by which it had already descended on the sundial of Ahaz, in reverse for ten degrees.

He brought the shadow ten degrees backward - We cannot suppose that these ten degrees meant ten hours; there were ten divisions of time on this dial: and perhaps it would not be right to suppose that the sun went ten degrees back in the heavens, or that the earth turned back upon its axis from east to west, in a contrary direction to its natural course. But the miracle might be effected by means of refraction, for a ray of light we know can be varied or refracted from a right line by passing through a dense medium; and we know also, by means of the refracting power of the atmosphere, the sun, when near rising and setting, seems to be higher above the horizon than he really is, and, by horizontal refraction, we find that the sun appears above the horizon when he is actually below it, and literally out of sight: therefore, by using dense clouds or vapors, the rays of light in that place might be refracted from their direct course ten, or any other number of degrees; so that the miracle might have been wrought by occasioning this extraordinary refraction, rather than by disturbing the course of the earth, or any other of the celestial bodies.
The dial of Ahaz - See the note on 2-Kings 9:13, and the observations and diagram at the end of this chapter.

And Isaiah the prophet cried unto the LORD: and he brought the shadow ten degrees backward, by which it had gone down in the (h) dial of Ahaz.
(h) Which was set at the top of the stairs that Ahaz had made.

And Isaiah the prophet cried unto the Lord,.... Or prayed, as the Targum; and was very earnest in prayer, that what Hezekiah had desired might be granted:
and he brought the shadow ten degrees backward, by which it had gone down in the dial of Ahaz; Ben Gersom understands it not of the sun itself, but of the shadow of it only; See Gill on Isaiah 38:8.

Isaiah then prayed to the Lord, and the Lord "turned back the shadow (caused it to go back) upon the sun-dial, where it had gone down, on the sundial of Ahaz, ten degrees backward." אחז מעלות cannot be understood, as it has been by the lxx, Joseph., Syr., as referring to a flight of steps at the palace of Ahaz, which was so arranged that the shadow of an object standing near indicated the hours, but is no doubt a gnomon, a sun-dial which Ahaz may have received from Babylonia, where sun-dials were discovered (Herod. ii. 109). Nothing further can be inferred from the words with regard to its construction, since the ancients had different kinds of sun-dials (cf. Martini Abhandlung von den Sonnenuhren der Alten, Lpz. 1777). The word מעלות steps in the literal sense, is transferred to the scala, which the shadow had to traverse both up and down upon the disk of the sun-dial, and is used both to denote the separate degrees of this scala, and also for the sum-total of these scala, i.e., for the sun-dial itself, without there being any necessity to assume that it was an obelisk-like pillar erected upon an elevated place with steps running round it (Knobel), or a long portable scale of twice ten steps with a gnomon (Gumpach, Alttestl. Studien, pp. 181ff.). All that follows from the descent of the shadow is that the dial of the gnomon was placed in a vertical direction; and the fact that the shadow went ten degrees down or backward, simply presupposes that the gnomon had at least twenty degrees, and therefore that the degrees indicated smaller portions of time than hours. If, then, it is stated in 2-Kings 20:8 of Isaiah that the sun went back ten degrees, whereas the going back of the shadow had been previously mentioned in agreement with our text, it is self-evident that the sun stands for the shining of the sun which was visible upon the dial-plate, and which made the shadow recede. We are not, of course, to suppose that the sun in the sky and the shadow on the sun-dial went back at the same time, as Knobel assumes. So far as the miracle is concerned, the words of the text do not require that we should assume that the sun receded, or the rotation of the earth was reversed, as Ephesians. Syr. and others supposed, but simply affirm that there was a miraculous movement backward of the shadow upon the dial, which might be accounted for from a miraculous refraction of the rays of the sun, effected by God at the prophet's prayer, of which slight analoga are met with in the ordinary course of nature.
(Note: As, for example, the phenomenon quoted by several commentators, which was observed at Metz in Lothringen in the year 1703 by the prior of the convent there, P. Romuald, and other persons, viz., that the shadow of a sun-dial went back an hour and a half. - The natural explanation of the miracle which is given by Thenius, who attributes it to an eclipse of the sun, needs no refutation. - For the different opinions of the earlier theologians, see Carpzov, Apparat. crit. p. 351ff.)
This miraculous sign was selected as a significant one in itself, to confirm the promise of a fresh extension of life which had been given to Hezekiah by the grace of God in opposition to the natural course of things. The retrograde movement of the shadow upon the sun-dial indicated that Hezekiah's life, which had already arrived at its close by natural means, was to be put back by a miracle of divine omnipotence, so that it might continue for another series of years.

Degrees - These degrees were lines in the dial: but whether each of these lines or degrees noted an hour, or half an hour, or a quarter of an hour, is uncertain. But the sun itself went back, and the shadow with it. This miracle was noted by the Babylonians, who, having understood that it was done for Hezekiah's sake, sent to enquire into the truth and manner of it, 2-Chronicles 32:31. Of Ahaz - Which Ahaz had made in the king's palace. This dial he mentions, because the truth of the miracle might be best and soonest discovered there, this dial possibly being visible out of the king's chamber, and the degrees being most distinct and conspicuous in it.