Yunus, 94 Ayah
10:94
فَإِن كُنتَ فِي شَكّٖ مِّمَّآ أَنزَلۡنَآ إِلَيۡكَ فَسۡـَٔلِ ٱلَّذِينَ يَقۡرَءُونَ ٱلۡكِتَٰبَ مِن قَبۡلِكَۚ لَقَدۡ جَآءَكَ ٱلۡحَقُّ مِن رَّبِّكَ فَلَا تَكُونَنَّ مِنَ ٱلۡمُمۡتَرِينَ ٩٤
Fa'in Kunta Fī Shakkin Mimmā 'Anzalnā 'Ilayka Fās'ali Al-Ladhīna Yaqra'ūna Al-Kitāba Min Qablika ۚ Laqad Jā'aka Al-Ĥaqqu Min Rabbika Falā Takūnanna Mina Al-Mumtarīna
So if you are in doubt, [O Muhammad], about that which We have revealed to you, then ask those who have been reading the Scripture before you. The truth has certainly come to you from your Lord, so never be among the doubters.