Al-Bara'at / At-Taubah (Repentance)
Surah 9 · Verse 118
and to the three who were left behind {4} (from going to the battle and whose condition became bad) to the extent that the earth, inspite of its spaciousness, became constrained on them and their souls (too) became constrained on them and they thought that there is no refuge from Allah except (in going) to Him. Then He turned to them (mercifully) that they may repent, Allah is certainly the Accepter of repentance, the Merciful. (R 14)
“Same to Verse No.117”
The three left behind during the expedition of Tabuk were Kab bin Malik, Halal bin Umayya and Mararah bin Rabi, they were all from Madina. Because they had not gone with the army of the Muslims they were cut off from the community for fifty days after which Allah finally forgive them.



