وَ رَوَى إِسْمَاعِيلُ بْنُ مُسْلِمٍ عَنِ اَلصَّادِقِ جَعْفَرِ بْنِ مُحَمَّدٍ عَنْ أَبِيهِ عَنْ آبَائِهِ عَنْ عَلِيٍّ عَلَيْهِ اَلسَّلاَمُ: "أَنَّ شَهَادَةَ اَلصِّبْيَانِ إِذَا شَهِدُوا وَ هُمْ صِغَارٌ جَازَتْ إِذَا كَبِرُوا مَا لَمْ يَنْسَوْهَا وَ كَذَلِكَ اَلْيَهُودُ وَ اَلنَّصَارَى إِذَا أَسْلَمُوا جَازَتْ شَهَادَتُهُمْ وَ اَلْعَبْدُ إِذَا أُشْهِدَ عَلَى شَهَادَةٍ ثُمَّ أُعْتِقَ جَازَتْ شَهَادَتُهُ إِذَا لَمْ يَرُدَّهَا اَلْحَاكِمُ قَبْلَ أَنْ يُعْتَقَ" وَ قَالَ عَلَيْهِ اَلسَّلاَمُ "إِنْ أُعْتِقَ اَلْعَبْدُ لِمَوْضِعِ اَلشَّهَادَةِ لَمْ تَجُزْ شَهَادَتُهُ".
And it was narrated by Isma'il ibn Muslim, from Imam Jafar ibn Muhammad Al-Sadiq (a.s), from his father Imam Muhammad ibn Ali Al-Baqir (a.s), from his forefathers, from Imam Ali ibn Abi Talib (a.s), who said: "The testimony of children, if they testified while they were young, is valid when they grow older as long as they have not forgotten it. Likewise, the testimony of Jews and Christians, if they embrace Islam, is valid. Also, the testimony of a slave, if he was made to testify and then was freed, is valid as long as the judge did not reject it before his emancipation." And Imam (a.s) said: "If the slave was freed specifically for the purpose of testimony, his testimony is not valid."