Surah At-Tawbah 9:42

لَوْ كَانَ عَرَضًا قَرِيبًا وَسَفَرًا قَاصِدًا لَّٱتَّبَعُوكَ وَلَـٰكِنۢ بَعُدَتْ عَلَيْهِمُ ٱلشُّقَّةُ ۚ وَسَيَحْلِفُونَ بِٱللَّهِ لَوِ ٱسْتَطَعْنَا لَخَرَجْنَا مَعَكُمْ يُهْلِكُونَ أَنفُسَهُمْ وَٱللَّهُ يَعْلَمُ إِنَّهُمْ لَكَـٰذِبُونَ

Had it been a near [i.e., easy] gain and a moderate trip, they [i.e., the hypocrites] would have followed you, but distant to them was the journey. And they will swear by Allāh, "If we were able, we would have gone forth with you," destroying themselves [through false oaths], and Allāh knows that indeed they are liars.

Translation: Saheeh International

Tafsir

The following was revealed regarding the hypocrites who stayed behind away from the campaign Had it — that to which you summon them — been a near easily acquired gain a transient pleasure of this world and an easy journey of moderate length they would have followed you seeking spoils; …

Excerpt from Tafsir al-Jalalayn, commentary on 9:42, via Quran.com. The reader has the full commentary and 9 more tafsirs.