At-Tawba 9:118

[And Allah also turned in mercy to] the three who stayed behind[86], until the earth became constrained to them, despite its vastness, and their souls became a burden to them, and they realized that there was no refuge from Allah except in Him. Then He turned to them in mercy, so that they might repent, for Allah is the Accepter of Repentance, the Most Merciful.

[86] Or whose cases were deferred. They were: Ka‘b ibn Mālik, Hilāl ibn ’Umayyah and Murārah ibn al-Rabī‘, who were sincere Companions but failed to join the Messenger’s (ﷺ) campaign in Tabūk Expedition. When he came back, unlike the hypocrites, they told the truth that they had no excuse. So, the Messenger (ﷺ) imposed a ban on them and forbade people to talk to them. This lasted for fifty nights until this verse was revealed. During this time, they endured huge mental anguish for being ostracized by the whole society. [For further details see: Al-Bukhārī: 4418, and Muslim: 2769]

And [He also forgave] the three who were left alone [i.e., boycotted, regretting their error] to the point that the earth closed in on them in spite of its vastness[505] and their souls confined [i.e., anguished] them and they were certain that there is no refuge from Allāh except in Him. Then He turned to them so they could repent. Indeed, Allāh is the Accepting of Repentance,[506] the Merciful.

[505] Thus it seemed to them in their extreme distress.
[506] Refer to footnote in 2:37.

118. And (He did forgive also) the three [who did not join the Tabûk expedition whose case was deferred (by the Prophet صلى الله عليه وسلم)] (for Allâh’s Decision) till for them the earth, vast as it is, was straitened and their ownselves were straitened to them, and they perceived that there is no fleeing from Allâh, and no refuge but with Him. Then, He forgave them (accepted their repentance), that they might beg for His pardon [repent (unto Him)] Verily, Allâh is the One Who forgives and accepts repentance, Most Merciful.

And to the three also (did He turn in mercy) who were left behind, when the earth, vast as it is, was straitened for them, and their own souls were straitened for them till they bethought them that there is no refuge from Allah save toward Him. Then turned He unto them in mercy that they (too) might turn (repentant unto Him). Lo! Allah! He is the Relenting, the Merciful.