Al-Kāfi
Hadith 5614- عَلِيُّ بْنُ إِبْرَاهِيمَ عَنْ أَبِيهِ عَنْ إِسْمَاعِيلَ بْنِ مَرَّارٍ وَغَيْرِهِ عَنْ يُونُسَ عَنْ بَعْضِ أَصْحَابِهِ عَنْ أَبِي عَبْدِ اللهِ (عَلَيْهِ السَّلام) قَالَ إِذَا سَمِعَ الرَّجُلُ الشَّهَادَةَ فَلَمْ يُشْهَدْ عَلَيْهَا فَهُوَ بِالْخِيَارِ إِنْ شَاءَ شَهِدَ وَإِنْ شَاءَ سَكَتَ إِلا إِذَا عَلِمَ مِنَ الظَّالِمِ فَيَشْهَدُ وَلا يَحِلُّ لَهُ أَنْ لا يَشْهَدَ.
4. Ali ibn Ibrahim has narrated from his father from ’Isma‘il ibn Marrar and others from Yunus from certain persons of his people who has narrated the following: “Abu ‘Abd Allah (a.s.), has said, ‘If a man hears a testimony but has not witnessed it, he has the choice to testify or remain silent, unless he knows that a rightful party suffers injustice, in which case it is not lawful to remain silent.’”