Tafsir of At-Tawbah 9:49

{ائذن لي} "Give me permission" to stay behind.

{ولا تفتني} "And do not expose me to fitnah (trial/sin)." Do not cause me to fall into sin by refusing to grant me permission, for if I stay behind without your leave, I will be sinful.

It is also said: "Do not cast me into ruin," for if I go out with you, my wealth and family will perish.

It is also said that Al-Jadd ibn Qays said: "The Ansar know that I am obsessed with women, so do not expose me to the 'daughters of Al-Asfar' (the Roman women), for I will be tempted. Instead, I will assist you with my wealth, so leave me behind."

It is also recited as (wa-la taftinī) from the verb aftana.

{ألا في الفتنة سقطوا} "Indeed, they have fallen into fitnah." That is, the fitnah is precisely what they have fallen into, which is the fitnah of staying behind.

In the Mushaf of Ubayy (may Allah be pleased with him), it is written as saqata (singular), because the word man (whoever/some) is singular in form but plural in meaning.

{وإن جهنم لمحيطة بالكافرين} "And indeed, Hell will encompass the disbelievers." This means it will encompass them on the Day of Resurrection. Or, it is encompassing them even now, because the causes of that encompassing are already with them, as if they are already in its midst.

{إن تصبك حسنة تسؤهم وإن تصبك مصيبة يقولوا قد أخذنا أمرنا من قبل ويتولوا وهم فرحون} "If good befalls you, it distresses them; but if disaster strikes you, they say, 'We had already taken our precautions beforehand,' and they turn away, rejoicing."