Ali 'Imran 3:81

وَإِذۡ أَخَذَ ٱللَّهُ مِيثَٰقَ ٱلنَّبِيِّـۧنَ لَمَآ ءَاتَيۡتُكُم مِّن كِتَٰبٖ وَحِكۡمَةٖ ثُمَّ جَآءَكُمۡ رَسُولٞ مُّصَدِّقٞ لِّمَا مَعَكُمۡ لَتُؤۡمِنُنَّ بِهِۦ وَلَتَنصُرُنَّهُۥۚ قَالَ ءَأَقۡرَرۡتُمۡ وَأَخَذۡتُمۡ عَلَىٰ ذَٰلِكُمۡ إِصۡرِيۖ قَالُوٓاْ أَقۡرَرۡنَاۚ قَالَ فَٱشۡهَدُواْ وَأَنَا۠ مَعَكُم مِّنَ ٱلشَّـٰهِدِينَ 81

And [recall, O People of the Scripture], when Allah took the covenant of the prophets, [saying], "Whatever I give you of the Scripture and wisdom and then there comes to you a messenger confirming what is with you, you [must] believe in him and support him." [Allah] said, "Have you acknowledged and taken upon that My commitment?" They said, "We have acknowledged it." He said, "Then bear witness, and I am with you among the witnesses