Story of how Abu Bakr became known as Abu Bakr al-Siddiq, "If he said that, then I believe him."
[Machine] When the Prophet Muhammad (pbuh) was taken on the Night Journey to the Al-Aqsa Mosque, people began talking about it. Some people turned away from believing it, but those who believed and confirmed it went to Abu Bakr and asked him, "Does your friend claim that he was taken on this journey to Al-Masjid Al-Aqsa last night?" Abu Bakr asked, "Did he say that?" They replied, "Yes." Abu Bakr said, "If he said that, then he has spoken the truth." They asked him, "Do you believe him when he says that he went to Al-Masjid Al-Aqsa last night and returned before morning?" Abu Bakr replied, "Yes, I believe him even in something far greater than that. I believe him when he receives revelation from the heavens, either during the morning or while at rest." That is why Abu Bakr was given the title "As-Siddiq" (the Truthful).
لَمَّا أُسْرِيَ بِالنَّبِيِّ ﷺ إِلَى الْمَسْجِدِ الْأَقْصَى أَصْبَحَ يَتَحَدَّثُ النَّاسُ بِذَلِكَ فَارْتَدَّ نَاسٌ فَمَنْ كَانَ آمَنُوا بِهِ وَصَدَّقُوهُ وَسَمِعُوا بِذَلِكَ إِلَى أَبِي بَكْرٍ فَقَالُوا هَلْ لَكَ إِلَى صَاحِبِكَ يَزْعُمُ أَنَّهُ أُسْرِيَ بِهِ اللَّيْلَةَ إِلَى بَيْتِ الْمَقْدِسِ قَالَ أَوَ قَالَ ذَلِكَ؟ قَالُوا نَعَمْ قَالَ لَئِنْ كَانَ قَالَ ذَلِكَ لَقَدْ صَدَقَ قَالُوا أَوَ تُصَدِّقُهُ أَنَّهُ ذَهَبَ اللَّيْلَةَ إِلَى بَيْتِ الْمَقْدِسِ وَجَاءَ قَبْلَ أَنْ يُصْبِحَ؟ قَالَ نَعَمْ إِنِّي لَأَصُدِّقُهُ فِيمَا هُوَ أَبْعَدُ مِنْ ذَلِكَ أُصَدِّقُهُ بِخَبَرِ السَّمَاءِ فِي غَدْوَةٍ أَوْ رَوْحَةٍ فَلِذَلِكَ سُمَيَّ أَبُو بَكْرٍ الصِّدِّيقَ