Surah Al-Baqarah, ayah 140

أَمۡ تَقُولُونَ إِنَّ إِبۡرَٰهِـۧمَ وَإِسۡمَٰعِيلَ وَإِسۡحَٰقَ وَيَعۡقُوبَ وَٱلۡأَسۡبَاطَ كَانُواْ هُودًا أَوۡ نَصَٰرَىٰۗ قُلۡ ءَأَنتُمۡ أَعۡلَمُ أَمِ ٱللَّهُۗ وَمَنۡ أَظۡلَمُ مِمَّن كَتَمَ شَهَٰدَةً عِندَهُۥ مِنَ ٱللَّهِۗ وَمَا ٱللَّهُ بِغَٰفِلٍ عَمَّا تَعۡمَلُونَ ١٤٠

Am taqūlūna inna ibrāhima wa ismā'īla wa ishāqa waya'qūba wal-asbāta kānū hūdan aw nasārā qul a'antum a'lamu amillāhu waman azlamu mimman katama shahādatan 'indahū minallāhi wamallāhu bighāfilin 'ammā ta'malūn

Or do you say that Abraham and Ishmael and Isaac and Jacob and the Descendants were Jews or Christians? Say, "Are you more knowing or is Allāh?" And who is more unjust than one who conceals a testimony⁴⁹ he has from Allāh? And Allāh is not unaware of what you do.