Can the imam be elevated above the congregation?

Hazrat Hammam narrates that Hazrat Hudhaifa (may Allah be pleased with him) began to lead the prayer from an elevated place, while the rest of the people were standing below. Hazrat Salman pulled him down from there. When they finished the prayer, Hazrat Salman said, "Do you not know that your companions used to consider it disliked for the imam to stand on something elevated while the people are below?" Hazrat Hudhaifa (may Allah be pleased with him) said, "That is absolutely correct. When you pulled me down, I remembered this matter."

Ibrahim narrates that Hazrat Hudhaifa (may Allah be pleased with him) stood on a high place in Madain and intended to lead the prayer from above his followers, so Hazrat Abu Mas'ud pulled him and said, "Do you not know that doing so is disliked?" He replied, "When you reminded me, I remembered!"

Hazrat Abdullah considered it undesirable for the imam to stand higher than his followers.

Hazrat Qasim narrates that there was a raised platform for the Imam, upon which he would stand and lead the prayer. Hazrat Abdullah disliked this and ordered it to be demolished.

Ibrahim considered it disliked for the place of the imam to be elevated above the place of the people. He also disliked that a person should place something elevated in the place of prayer and prostrate on it.

Hazrat Bilal Absi narrates that Hazrat Ammar saw a man praying on a high place, so he grabbed him by the neck and brought him down, and said, "Pray here."

Hazrat Usman bin Abi Hind narrates that I saw Hazrat Umar bin Abdul Aziz standing on a high place in Syria leading the prayer, while the people were below.

Hasan did not see any harm in the imam standing on a higher place than the followers while leading the prayer.