Ladder

And if their evasion is difficult for you, then if you are able to seek a tunnel into the earth or a stairway into the sky to bring them a sign, [then do so]. But if Allāh had willed, He would have united them upon guidance. So never be of the ignorant.

And if it were not that the people would become one community [of disbelievers],¹ We would have made for those who disbelieve in the Most Merciful - for their houses - ceilings and stairways of silver upon which to mount.

Or have they a stairway [into the heaven] upon which they listen? Then let their listener produce a clear authority [i.e., proof].