Matam is an expression of grief and sadness which is used by human beings in different societies in different ways. The Prophet Muhammad ((SAWA) after the battle of Uhud, encouraged Muslims to mourn on the martyrdom of his uncle Hamza when many Muslims were mourning their own martyrs by telling them : Why my uncle Hamza has no mourners? وعمّي حمزة لا بواكي له ؟ Musnad Ahmad Ibn Hanbal , Hadeeth number 4742 and Al-Mustadral Ala Al-Saheehain; Hadeeth 1407, and Al-Mu'jam Al-Kabeer by Al-Tabarani; 11/310 , and Al-Tabaqaat Al-Khubra by Ibn Sa'ad; 2/44, and Tareekh Al-Tabari; 2/210.
'Matam was also done by Ayisha and Muslim women when the Prophet passed away. Musnad Ahmad ibn Hanbal , Hadeeth number 25144 and Dalaa'il Al-Nubowwah by Al-Bayhaqi (Al-Eltudaam (Beating the chest)).and Al-Tabaqaat Al-Khubra by ibn Sa'ad 2/261 and Tareekh Al-Tabari; 2/441 and Ibn Al-Atheer in Al-Bidayah Wal-Nihayah.
'Ahlul Bayt (AS) did Matam on Imam Husain (AS) as we read in Ziyarat Al-Naahiyah Al-Moqaddasa narrated from Imam Al-Mahdi (AS). لاطمات الصور
Wassalam.