Caution: Translations of Quran and Ḥadīth may lead to possible misapplications and misinterpretations. This site is intended for students of sacred knowledge that are proficient in comprehending classical Arabic and have a strong foundation in Islamic sciences. Also note that religious injunctions rely on several aspects beyond what one may glean through reading individual aḥādīth.
ibnmajah:2363ʿAbdullāh b. al-Jarrāḥ > Jarīr > ʿAbd al-Malik b. ʿUmayr > Jābir b. Samurah > Khaṭabanā ʿUmar b. al-Khaṭṭāb Bi-al-Jābiyah

'Umar bin Khattab addressed us at Jabiyah and said: “The Messenger of Allah ﷺ stood up among us as I stand among you, and said: 'Honor my Companions for my sake, then those who come after them, then those who come after them. Then lying will prevail until a man will give testimony without being asked to do so, and he will swear an oath without being asked to do so.' ”  

ابن ماجة:٢٣٦٣حَدَّثَنَا عَبْدُ اللَّهِ بْنُ الْجَرَّاحِ حَدَّثَنَا جَرِيرٌ عَنْ عَبْدِ الْمَلِكِ بْنِ عُمَيْرٍ عَنْ جَابِرِ بْنِ سَمُرَةَ قَالَ خَطَبَنَا عُمَرُ بْنُ الْخَطَّابِ بِالْجَابِيَةِ فَقَالَ

إِنَّ رَسُولَ اللَّهِ ﷺ قَامَ فِينَا مِثْلَ مُقَامِي فِيكُمْ فَقَالَ احْفَظُونِي فِي أَصْحَابِي ثُمَّ الَّذِينَ يَلُونَهُمْ ثُمَّ الَّذِينَ يَلُونَهُمْ ثُمَّ يَفْشُو الْكَذِبُ حَتَّى يَشْهَدَ الرَّجُلُ وَمَا يُسْتَشْهَدُ وَيَحْلِفَ وَمَا يُسْتَحْلَفُ  


See similar narrations below:

Collected by Suyūṭī
suyuti:735a

'Umar bin Khattab addressed us at Jabiyah and said: “The Messenger of Allah ﷺ stood up among us as I stand among you, and said: 'Honor my Companions for my sake, then those who come after them, then those who come after them. Then lying will prevail until a man will give testimony without being asked to do so, and he will swear an oath without being asked to do so.' ” (Using translation from Ibn Mājah 2363)   

السيوطي:٧٣٥a

"احفظونى في أصحابى، ثم الذين يلونهم، ثم الذين يلونهم، ثم يفشو الكذب، حتى يشهدَ الرجل وما يُسْتَشْهدُ، ويَحْلِف وما يُستحلف.  

[هـ] ابن ماجة عن عمر