﴿ وَيَصْنَعُ ٱلْفُلْكَ وَكُلَّمَا مَرَّ عَلَيْهِ مَلَأٌۭ مِّن قَوْمِهِۦ سَخِرُوا۟ مِنْهُ ۚ قَالَ إِن تَسْخَرُوا۟ مِنَّا فَإِنَّا نَسْخَرُ مِنكُمْ كَمَا تَسْخَرُونَ ﴾

“And [so Noah] set himself to building the ark; and every time the great ones of his people passed by him, they scoffed at him. [Thereupon] he said: "If you are scoffing at us-behold, we are scoffing at you [and your ignorance], just as you are scoffing at us.”

And he was building the Ark yasna‘ is narrating a past state in the present tense and whenever a council a group of his people passed him they scoffed at him mocked him. He said ‘Though you scoff at us yet we scoff at you even as you scoff when we are saved while you drown;