Bulūgh is the age where Sharia responsibilities become incumbent on an individual. The Quran does not specify any criteria for the age of bulūgh nor does it provide any signs or indication as to when an individual reaches this stage. A significant amount of hadith literature concludes that seminal discharge for boys and menstruation for girls are the indicators that an individual has reached bulūgh. (Al-Kāfī, vol. 4, p. 276, vol. 7, p. 69; p. 198; Tahdhīb al-aḥkām, vol. 2, p. 381, vol. 6, p. 310; vol. 7, p. 383; Al-faqīh, vol. 2, p. 122)

Sharia dictates are commonly categorised into devotional responsibilities (ʿibādāt) and social responsibilities (muʿāmalāt). Sharia social responsibilities were constructed to regulate social practices and transactions in order to minimise injustice and potential abuse. Accordingly, the law of land has the authority to regulate the affairs of its citizens and decide on the age of responsibility, for example, when an individual can enter into marriage or can be held as criminally responsible.
The age of bulūgh for devotional Sharia responsibilities (ʿibādāt), such as the daily prayers, fasting during Ramadan, and performing hajj, is determined by the physiological changes occurring in the body of an individual such as seminal discharge for boys and menstruation for girls. However, there is no obligation on performing any duty unless the ability of enactment (wusʿ) is ascertained. This is established by the Quran (2:233, 2:286, 6:152, 7:42, 23:62). For example, although the obligation of performing hajj is incumbent on a young girl from when she begins menstruating, she may not necessarily have the required ability to adequately discharge the obligation.