Qur'an 2:248 · Al-Baqara

وَقَالَ لَهُمْ نَبِيُّهُمْ إِنَّ ءَايَةَ مُلْكِهِۦٓ أَن يَأْتِيَكُمُ ٱلتَّابُوتُ فِيهِ سَكِينَةٌۭ مِّن رَّبِّكُمْ وَبَقِيَّةٌۭ مِّمَّا تَرَكَ ءَالُ مُوسَىٰ وَءَالُ هَٰرُونَ تَحْمِلُهُ ٱلْمَلَٰٓئِكَةُ ۚ إِنَّ فِى ذَٰلِكَ لَءَايَةًۭ لَّكُمْ إِن كُنتُم مُّؤْمِنِينَ

(248) And their prophet said to them, "Indeed, a sign of his kingship is that the chest will come to you in which is assurance[97] from your Lord and a remnant of what the family of Moses and the family of Aaron had left, carried by the angels. Indeed in that is a sign for you, if you are believers."