Ta’ziyat is to offer condolence to the closed relatives of the deceased.
In Kitaab Zaheeriyyah it is stated that Ta’ziyat is an act of much merit. Rasulullah ﷺ said:
“He who consoles one afflicted with sadness, Allah will cloak him with the garments of piety and Allah will have mercy of his soul.”
Hadhrat Imam Hasan bin Ziyad says that Ta’ziyat should be made once only. It is not an act to be repeated.
The time in which Ta’ziyat is valid, is the period of three days from the time of death. After the expiry of three days it is Makrooh to offer Ta’ziyat. However, if one happens to be absent during this period or the concerned relative of the desceased is absent then Ta’ziyat could be made at any time after the three days have expired.
It is “aulaa” (best and of greater merit) to offer one’s condolence after burial, not before burial although it is permissible. However, if the relatives of the deceased are overcome with extreme grief then making Ta’ziyat before burial will be appropriate.
In Siraajul Wihaaj it is said:
“It is Mustahab to offer condolence to all the relatives of the mayyit excepting young women (Ta’ziyat will not be offered to them). Only the mahaareem of the young women may offer Ta’ziyat to them.”
It is Mustahab for the one offering condolence to say to the relatives:
Ghafaral-lahu Ta’alaa li may-yitika wa ta jaawaza anhu wa tagham-madahu bi rah mati hi wa razaqa kas sabra alaa museebatika wa ajara ka alaa mautihi
Translation: May Allah Ta’ala forgive your Mayyit; and overlook his (faults); and cover him in His Mercy; and grant you patience over his difficulty, and may He reward you over his (the mayyit’s) death.”