﴿ مَا قُلْتُ لَهُمْ إِلَّا مَآ أَمَرْتَنِى بِهِۦٓ أَنِ ٱعْبُدُوا۟ ٱللَّهَ رَبِّى وَرَبَّكُمْ ۚ وَكُنتُ عَلَيْهِمْ شَهِيدًۭا مَّا دُمْتُ فِيهِمْ ۖ فَلَمَّا تَوَفَّيْتَنِى كُنتَ أَنتَ ٱلرَّقِيبَ عَلَيْهِمْ ۚ وَأَنتَ عَلَىٰ كُلِّ شَىْءٍۢ شَهِيدٌ ﴾

“Nothing did I tell them beyond what Thou didst bid me [to say]: `Worship God, [who is] my Sustainer as well as your Sustainer.' And I bore witness to what they did as long as I dwelt in their midst; but since Thou hast caused me to die, Thou alone hast been their keeper: for Thou art witness unto everything.”

Please check ayah 5:118 for complete tafsir.