Surah Ash-Shu'ara, ayah 194

عَلَىٰ قَلۡبِكَ لِتَكُونَ مِنَ ٱلۡمُنذِرِينَ ١٩٤

'Alā qalbika litakūna minal-mundhirīn

Upon your heart, [O Muḥammad] - that you may be of the warners