What procedure validates the accuracy and experience of a *Qā'if*?

Primary text

The knowledge of the *Qā'if* must be confirmed through practical testing (*tajriba*). One test involves presenting a child, whose lineage is disputed, among ten men, none of whom is the alleged father. If the *Qā'if* incorrectly attributes the child to one of these ten, their testimony is invalidated. If the child is correctly not assigned to any of them, a second test involves presenting the child among twenty men, including the actual claimant. If the *Qā'if* correctly identifies the claimant, their expertise is confirmed. Alternatively, testing can involve presenting a child of known lineage with his true father or brother; if the *Qā'if* matches the child to the relative, accuracy is established. However, if the individual is already renowned for great accuracy over many instances, the immediate practical test is dispensable for acceptance.