If the Prophet ﷺ did not disapprove of something

Narrated Muhammad bin Al-Munkadir:

I saw Jabir bin 'Abdullah swearing by Allah that Ibn Sayyad was the Dajjal. I said to Jabir, "How can you swear by Allah?" Jabir said, "I have heard 'Umar swearing by Allah regarding this matter in the presence of the Prophet and the Prophet did not disapprove of it."

حَدَّثَنَا حَمَّادُ بْنُ حُمَيْدٍ، حَدَّثَنَا عُبَيْدُ اللَّهِ بْنُ مُعَاذٍ، حَدَّثَنَا أَبِي، حَدَّثَنَا شُعْبَةُ، عَنْ سَعْدِ بْنِ إِبْرَاهِيمَ، عَنْ مُحَمَّدِ بْنِ الْمُنْكَدِرِ، قَالَ رَأَيْتُ جَابِرَ بْنَ عَبْدِ اللَّهِ يَحْلِفُ بِاللَّهِ أَنَّ ابْنَ الصَّائِدِ الدَّجَّالُ، قُلْتُ تَحْلِفُ بِاللَّهِ. قَالَ إِنِّي سَمِعْتُ عُمَرَ يَحْلِفُ عَلَى ذَلِكَ عِنْدَ النَّبِيِّ ﷺ فَلَمْ يُنْكِرْهُ النَّبِيُّ ﷺ.