“Isaiah the prophet called out to the Lord, and the Lord made the shadow go back ten steps on the stairs of Ahaz.” (2 Kings 20:11 NET)
THE STAIRS OF AHAZ
There are various viewpoints as to whether this was a sundial or a stairway. The word means “a step, stairs, an ascent” but has been translated as
- “sundial” (NKJV, AMP, NLT)
- “dial” (KJV)
- “step” (ESV)
- “stairway” (NASU, NIV)
The article “Sundial Types” describes the different types of sundials and the methods each used to mark the hours of the day. Yet there is no requirement that the “stairs of Ahaz” were used to mark time.
- The Bible Background Commentary states, “The text here does not mention that the structure was used to tell time.”
- The Bible Background Commentary states, “The structure may have been simply steps leading to a roof or higher structure where shadows were cast at a certain time of the day.”
PURPOSE OF THE “STAIRS OF AHAZ”
- The purpose of the “stairs of Ahaz” may have been part of the worship of Baal, for everything that Ahaz did was to promote the worship of the pagan gods: “He walked in the ways of the kings of Israel; he also made molten images for the Baals. Moreover, he burned incense in the valley of Ben-hinnom and burned his sons in fire, according to the abominations of the nations whom the Lord had driven out before the sons of Israel. He sacrificed and burned incense on the high places, on the hills and under every green tree.” (2 Chronicles 28:2-4 NASU)
- The Tyndale Old Testament Commentary describes the “stairs of Ahaz” as “an upper chamber was used perhaps for celestial observations for guiding decisions. Ahaz may have introduced such practices in the temple area”
- The Faithlife Study Bible describes the “stairs of Ahaz” as “perhaps a reference to a sundial - possibly connected to worship of the sun, moon, and stars - on the roof of Ahaz’s upper chamber.
Agricultural cycles and the worship of pagan gods were tightly linked, and the use of devices to tell the time of day and time of year would be tightly linked with the worship of pagan gods, including Baal.
- Easton’s Bible Dictionary states, “The sun-god, under the general title of Baal, or “lord,” was the chief object of worship of the Canaanites.” 
- The International Standard Bible Encyclopedia states, “The Râs Shamrah texts praise Baal as the god who has power over rain, wind, clouds, and therefore over fertility”
- The Tyndale Bible Dictionary states, “As the god of fertility in the Canaanite pantheon (roster of gods), Baal’s sphere of influence included agriculture, animal husbandry, and human sexuality
Some argue that events of this type occur “naturally”:
- Adam Clarke's Commentary states, “Some Hollanders, who wintered in Nova Zembla in the year 1596, were surprised to find that after a continual night of three months, the sun began to rise seventeen days sooner than (according to computation deduced from the altitude of the pole, observed to be seventy-six degrees) he should have done; which can only be accounted for by a miracle, or by an extraordinary refraction of the sun's rays passing through the cold dense air in that climate.”
- Barnes’ Commentary states, “Recently, it has been urged that the true cause of the phenomenon was a solar eclipse.”
Even if the going back of the shadow was a so-called “natural” event, the ability of Isaiah to state exactly when this “natural” event would occur was a miracle:
- Barnes’ Commentary states, “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.”
- Adam Clarke's Commentary states, “Infidelity must be driven to pitiful shifts when it is obliged to have recourse to the insinuation of imposture, in a case where the miraculous interference of God is so strikingly evident.”
“The Sign to Hezekiah”
EFFECT ON TIME
The passage does not require that time itself be reversed:
- The Keil and Delitzsch Commentary states, “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 Eph. 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.” 
- The Teacher's Bible Commentary states, “The Scripture does not say that the sun went backward or that the earth reversed its rotation on its axis. The miracle had to do with a moving backward of a shadow. God can do all things, of course, but this passage does not say that God placed the machinery of the universe in reverse.”
- The McClintock and Strong Encyclopedia states, “Certainly no necessity for supposing any actual interference with the revolution of the earth, or the position of the sun … it is not said that any time was lost to the inhabitants of the world at large.”
- The Teacher's Bible Commentary states, “The Bible does say that the shadow was moved back. Some interpreters say God’s glory illuminated the area, moving the shadow in reverse.”
Yet others think this caused an effect on time. The Cambridge Bible for School and Colleges states, “Thus reversing the order of nature.”
ONLY OBSERVED LOCALLY?
Some interpret this sign as something seen only by those in Jerusalem.