I will make the sun’s shadow that falls on the stairway of Ahaz go back ten steps.’” So the sunlight went back the ten steps it had descended.
KJV
Behold, I will bring again the shadow of the degrees, which is gone down in the sun dial of Ahaz, ten degrees backward. So the sun returned ten degrees, by which degrees it was gone down.
ASV
behold, I will cause the shadow on the steps, which is gone down on the dial of Ahaz with the sun, to return backward ten steps. So the sun returned ten steps on the dial whereon it was gone down.