Al-Muddaththir • EN-AL-JALALAYN
﴿ سَأُرْهِقُهُۥ صَعُودًا ﴾
“[and so] I shall constrain him to endure a painful uphill climb!”
Soon I shall burden him with a trying chastisement; alternatively sa‘ūdan means a mountain of fire which he will be made to ascend and then fall down from forever.