Yunus 94

فَإِن كُنتَ فِى شَكٍّ مِّمَّآ أَنزَلْنَآ إِلَيْكَ فَسْـَٔلِ ٱلَّذِينَ يَقْرَءُونَ ٱلْكِتَٰبَ مِن قَبْلِكَ لَقَدْ جَآءَكَ ٱلْحَقُّ مِن رَّبِّكَ فَلَا تَكُونَنَّ مِنَ ٱلْمُمْتَرِينَ ﴿٩٤﴾

Fain kunta fee shakkin mimma anzalnna ilayka faisali allatheena yaqraoona alkitaba min qablika laqad jaaka alhaqqu min rabbika fala takoonanna mina almumtareena

So if you (O Muhammad SAW) are in doubt concerning that which We have revealed unto you, [i.e. that your name is written in the Taurat (Torah) and the Injeel (Gospel)] then ask those who are reading the Book [the Taurat (Torah) and the Injeel (Gospel)] before you. Verily, the truth has come to you from your Lord. So be not of those who doubt (it). The Noble Quran