“Do not slaughter except a musinnah (a fully mature animal), unless it is difficult for you, in which case you may slaughter a jadhʿah (a young) sheep.”

Narrated by Muslim (no. 1963) from the ḥadīth of Jābir ibn ʿAbd Allāh (may Allah be pleased with him).

Brief Explanation of the Hadith

Uḍḥiyah is a great act of worship and a manifest rite of Islam. Its validity is contingent upon specific rulings and conditions, among them the legally required age of the sacrificial animal. This is indicated by the saying of the Prophet (may Allah’s peace and blessings be upon him): “Do not slaughter except a musinnah.” A musinnah is the thanīyyah from each type of livestock—an animal that has developed the distinguishing tooth by which reaching the legally recognized age is known. Thus, from camels: that which has completed five years; from cattle: that which has completed two years; and from sheep/goats: that which has completed one year. His statement, “unless it is difficult for you,” means: if procuring a musinnah from sheep is burdensome—due to high cost, unavailability, or scarcity—then “slaughter a jadhʿah from sheep,” meaning that, in such a case, permission is granted to slaughter a jadhʿah from sheep, which is an animal that has completed six months and entered the seventh.
The hadith is explicit in indicating that a musinnah or older is required for a valid sacrifice; thus, a jadhʿah from camels or cattle does not suffice, nor does a jadhʿah from sheep—except in the case where a musinnah is unavailable. A group of scholars, however, held that a jadhʿah from sheep is valid in all cases, based on the statement of the Prophet (may Allah’s peace and blessings be upon him): “Indeed, the jadhʿah suffices as does the thaniyyah,” narrated by Abu Dāwud and al-Nasā’i. They interpreted the ḥadīth of Jābir (may Allah be pleased with him) as indicating preference rather than obligation, thereby reconciling the evidences.
The ruling of the hady is the same as that of the uḍḥiyah, for they are equal with respect to the required age; whatever is valid for one is valid for the other, and whatever is invalid for one is likewise invalid for the other.