Hadith on Marriage: Lawful marriage must be announced publicly

Muhammad ibn Hatib reported: The Messenger of Allah, peace and blessings be upon him, said, “The difference between an unlawful and lawful marriage is the beating of drums and raising of voices.”

Source: Sunan al-Tirmidhī 1088

Grade: Hasan (fair) according to Al-Albani

Abu Bakr Abdul Aziz said, “A secret marriage is invalid, as Ahmad said: If he is married with a guardian’s permission and two witnesses, it is not so valid until it is announced publicly.”

Source: al-Mughnī 7/83

عَنْ مُحَمَّدِ بْنِ حَاطِبٍ الْجُمَحِيِّ قَالَ قَالَ رَسُولُ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ فَصْلُ مَا بَيْنَ الْحَرَامِ وَالْحَلَالِ الدُّفُّ وَالصَّوْتُ

1088 سنن الترمذي كتاب النكاح باب ما جاء في إعلان النكاح

1088 المحدث الذهبي خلاصة حكم المحدث حسن في صحيح الترمذي

وَقَالَ أَبُو بَكْرٍ عَبْدُ الْعَزِيزِ نِكَاحُ السِّرِّ بَاطِلٌ لِأَنَّ أَحْمَدَ قَالَ إذَا تَزَوَّجَ بِوَلِيٍّ وَشَاهِدَيْنِ لَا حَتَّى يُعْلِنَهُ

7/83 المغني لابن قدامة