Had they gone forth with you, they would not have increased you (9:47)

﴿لَوْ خَرَجُوا فِيكُم مَّا زَادُوكُمْ إِلَّا خَبَالًا وَلَأَوْضَعُوا خِلَالَكُمْ يَبْغُونَكُمُ الْفِتْنَةَ وَفِيكُمْ سَمَّاعُونَ لَهُمْ ۗ وَاللَّهُ عَلِيمٌ بِالظَّالِمِينَ﴾
[ التوبة: 47]

9:47 Had they gone forth with you, they would not have increased you except in confusion, and they would have been active among you, seeking [to cause] you fitnah. And among you are avid listeners to them. And Allah is Knowing of the wrongdoers.

It was a blessing that these hypocrites did not go with them, because if they had gone they would only have increased them in problems: demoralising people and making them doubt, hurrying between their lines, spreading rumours to divide them.
Some of the believers would listen to such lies, believing and repeating them, causing arguments amongst them.
Allah knows the wrongdoers among the hypocrites, who try to spread conspiracies and doubts among the believers.

Had they marched out with you, they would have added to you nothing except disorder, and they would have hurried about in your midst (spreading corruption) and sowing sedition among you, and there are some among you who would have listened to them. And Allah is the All-Knower of the Zalimun (polytheists and wrong-doers, etc.).

phonetic Transliteration

Law kharajoo feekum ma zadookum illa khabalan walaawdaAAoo khilalakum yabghoonakumu alfitnata wafeekum sammaAAoona lahum waAllahu AAaleemun bialththalimeena

Abdullah Yusuf Ali - Translation

If they had come out with you, they would not have added to your (strength) but only (made for) disorder, hurrying to and fro in your midst and sowing sedition among you, and there would have been some among you who would have listened to them. But Allah knoweth well those who do wrong.

Safi-ur-Rahman al-Mubarakpuri

Had they marched out with you, they would have added to you nothing except disorder, and they would have hurried about in your midst (spreading corruption) and sowing sedition among you -- and there are some among you who would have listened to them. And Allah is the All-Knower of the wrongdoers.

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