while what affects undertaking testimony is ignorance, and what affects delivering it is forgetfulness. A person must guard against both. As for undertaking testimony, the author says:
“Undertaking testimony in matters other than the rights of Allah is a collective obligation. If no sufficient number of people is available, it becomes individually obligatory upon the one who is available. Delivering it is an individual obligation upon whoever has undertaken it, whenever he is summoned to do so.”
His statement, “Undertaking testimony in matters other than the rights of Allah is a collective obligation,” means that undertaking testimony is assuming the obligation to give it. In matters other than the rights of Allah, it is a collective obligation. Thus, if someone asks you to testify that Zayd has acknowledged a right due to him, then giving such testimony is a collective obligation: if a sufficient number of people undertake it, the obligation is waived from the rest; otherwise, it becomes obligatory upon them. This is why he says:
“And if no sufficient number of people is available, it becomes individually obligatory upon the one who is available.” Someone may summon you to testify that Zayd has acknowledged a right due to him, and no one else is present besides you; in that case, you must respond, because no one else is available to fulfil the collective obligation. Or he may summon you to testify alongside him, while there is only one other witness besides you; then it becomes obligatory upon you.
The difference between undertaking testimony and delivering it is that a person has not committed himself to the former, and it is not binding upon him unless no one else is available. As for delivering testimony, he has already committed himself by undertaking it, and so he must deliver it.
If he says, “You have a witness,” say: “Yes, but one witness is not sufficient.” If he then tells you, “A witness together with your oath is sufficient,” what should you say? Say:
First: This is a matter concerning which there is scholarly disagreement, and I fear that we may litigate before a judge who does not hold this view, in which case my right would be lost.
Second: The oath upon which judgment is based is only resorted to in cases of necessity. When someone is available to testify, there is no need for an oath.
Or he may summon you to testify for him, and you say, “His father is with you; he can testify for you.” We say: His testimony in his son’s favour is not accepted.