This verse is an objection, and the heavy saying refers to the Qur'an and what it contains of commands and prohibitions that are burdensome and heavy on those obligated, especially on the Messenger of Allah, blessings and peace be upon him, because he bears them himself and carries them for his nation. They are heavier on him and more burdensome for him. This objection intends to indicate that what he was commanded regarding the night prayer is among the heavy and difficult obligations mentioned in the Qur'an, because the night is a time of sleep, rest, and tranquility. Therefore, whoever revives it must oppose his nature and struggle against himself. Ibn Abbas, may Allah be pleased with him, said: When revelation descended upon him, it weighed heavily upon him. [This was narrated by Ahmad from the hadith of Ibn Abbas in the story of Ibn Umayyah. He said, 'When the Prophet, blessings and peace be upon him, received revelation, they would recognize that from the change in his skin.'] And Abu Nu'aym in the Dalail said, 'When revelation descended upon him, his face and body would change.' And there is a hadith from Ubadah ibn al-Samit: 'When the Messenger of Allah, blessings and peace be upon him, received revelation, he would feel distressed and his face would change.' [The term 'and his face would change' means he would frown.] And from Aisha, may Allah be pleased with her: I saw him receiving revelation on a very cold day, and he would break off from it while his forehead was dripping with sweat. [This is agreed upon from the hadith of Aisha.] And from al-Hasan: It is heavy in the balance. It was said: It is heavy on the hypocrites. It was said: It is a speech that has weight and significance, not trivial.