Sunan an-Nasa'i, Volume 5, Book 39, Hadith 4177 (DarusSalam) ⓘ
It was narrated that 'Abdullah bin Waqdan As-Sa'di said: "We came in a delegation to the messenger of Allah, each of us with a question to ask him. I was the last of them to come in to the Messenger of Allah, and I said: 'O Messenger of Allah, I have left people behind me, and they are saying that emigration (Hijrah) has ceased.' He said: 'Emigration will not cease so long as the disbelievers are being fought."'
أَخْبَرَنَا عِيسَى بْنُ مُسَاوِرٍ، قَالَ حَدَّثَنَا الْوَلِيدُ، عَنْ عَبْدِ اللَّهِ بْنِ الْعَلاَءِ بْنِ زَبْرٍ، عَنْ بُسْرِ بْنِ عُبَيْدِ اللَّهِ، عَنْ أَبِي إِدْرِيسَ الْخَوْلاَنِيِّ، عَنْ عَبْدِ اللَّهِ بْنِ وَاقِدٍ السَّعْدِيِّ، قَالَ وَفَدْتُ إِلَى رَسُولِ اللَّهِ صلى الله عليه وسلم فِي وَفْدٍ كُلُّنَا يَطْلُبُ حَاجَةً وَكُنْتُ آخِرَهُمْ دُخُولاً عَلَى رَسُولِ اللَّهِ صلى الله عليه وسلم فَقُلْتُ يَا رَسُولَ اللَّهِ إِنِّي تَرَكْتُ مَنْ خَلْفِي وَهُمْ يَزْعُمُونَ أَنَّ الْهِجْرَةَ قَدِ انْقَطَعَتْ . قَالَ " لاَ تَنْقَطِعُ الْهِجْرَةُ مَا قُوتِلَ الْكُفَّارُ " .
also referenced under: Hadith 4172 (Reference) & Book 39, Hadith 24 (In-Book)