That he heard the Prophet ﷺ on the day (of the battle) of Khaibar saying, "I will give the flag to a person at whose hands Allah will grant victory." So, the companions of the Prophet ﷺ got up, wishing eagerly to see to whom the flag will be given, and everyone of them wished to be given the flag. But the Prophet asked for ʿAli. Someone informed him that he was suffering from eye-trouble. So, he ordered them to bring ʿAli in front of him. Then the Prophet ﷺ spat in his eyes and his eyes were cured immediately as if he had never any eye-trouble. ʿAli said, "We will fight with them (i.e. infidels) till they become like us (i.e. Muslims)." The Prophet ﷺ said, "Be patient, till you face them and invite them to Islam and inform them of what Allah has enjoined upon them. By Allah! If a single person embraces Islam at your hands (i.e. through you), that will be better for you than the red camels." (Using translation from Bukhārī 2942)   

سَمِعْتُ رَسُولَ اللهِ ﷺ يَقُولُ يَوْمَ خَيْبَرَ لَأُعْطِيَنَّ الرَّايَةَ رَجُلًا يَفْتَحُ اللهُ عَلَى يَدَيْهِ فَبَاتَ النَّاسُ يَدُوكُونَ أَيُّهُمْ يُعْطَاهَا فَلَمَّا أَصْبَحَ النَّاسُ غَدَوْا عَلَى رَسُولِ اللهِ ﷺ كُلُّهُمْ يَرْجُو أَنْ يُعْطَاهَا فَقَالَ رَسُولُ اللهِ ﷺ أَيْنَ عَلِيُّ بْنُ أَبِي طَالِبٍ؟ قَالُوا يَا رَسُولَ اللهِ هُوَ يَشْتَكِي عَيْنَيْهِ فَأَرْسَلَ إِلَيْهِ فَبَصَقَ فِي عَيْنِهِ وَدَعَا لَهُ فَبَرَأَ مَكَانَهُ حَتَّى لَكَأَنَّهُ لَمْ يَكُنْ بِهِ شَيْءٌ فَأَعْطَاهُ الرَّايَةَ فَقَالَ يَا رَسُولَ اللهِ أُقَاتِلُهُمْ حَتَّى يَكُونُوا مِثْلَنَا قَالَ عَلَى رِسْلِكَ انْفُذْ حَتَّى تَنْزِلَ بِسَاحَتِهِمْ ثُمَّ ادْعُهُمْ إِلَى الْإِسْلَامِ وَأَخْبِرْهُمْ بِمَا يَجِبُ عَلَيْهِمْ فِيهِ مِنَ الْحَقِّ فَوَاللهِ لَأَنْ يَهْدِيَ اللهُ بِكَ الرَّجُلَ الْوَاحِدَ خَيْرٌ لَكَ مِنْ حُمْرِ النَّعَمِ  

[Machine] That the Messenger of Allah ﷺ wrote to Kisra and Caesar, and to every oppressive ruler, inviting them to Allah.  

أَنَّ رَسُولَ اللهِ ﷺ كَتَبَ إِلَى كِسْرَى وَقَيْصَرَ وَإِلَى كُلِّ جَبَّارٍ يَدْعُوهُمْ إِلَى اللهِ ﷻ  

[Machine] The Messenger of Allah ﷺ never fought a people until he invited them.  

مَا قَاتَلَ رَسُولُ اللهِ ﷺ قَوْمًا قَطُّ حَتَّى يَدْعُوَهُمْ  

[Machine] The Messenger of Allah ﷺ was brought captives from Al-Lat and Al-Uzza (pagan idols). The Messenger of Allah ﷺ asked them, "Did you call them to Islam?" They replied, "No." He then asked them, "Did they call you to Islam?" They again replied, "No." He said, "Leave them until they reach a place of safety." Then the Messenger of Allah ﷺ recited the following two verses: "Verily, We have sent you as a witness, a bringer of glad tidings, and a warner. And as one who invites to Allah by His permission, and as a lamp spreading light" (Quran 33:46) and "And it is revealed to me this Quran, that I may warn you thereby and whomever it reaches. Do you really bear witness that there are other gods with Allah?" (Quran 6:19) until the end of the verse. This hadith is narrated by Rawh ibn Musafer, who is considered weak.  

أُتِيَ رَسُولُ اللهِ ﷺ بِأُسَارَى مِنَ اللَّاتِ وَالْعُزَّى قَالَ فَقَالَ رَسُولُ اللهِ ﷺ هَلْ دَعَوْهُمْ إِلَى الْإِسْلَامِ؟ فَقَالُوا لَا فَقَالَ لَهُمْ هَلْ دَعَوْكُمْ إِلَى الْإِسْلَامِ؟ فَقَالُوا لَا قَالَ خَلُّوا سَبِيلَهُمْ حَتَّى يَبْلُغُوا مَأْمَنَهُمْ ثُمَّ قَرَأَ رَسُولُ اللهِ ﷺ هَاتَيْنِ الْآيَتَيْنِ {إِنَّا أَرْسَلْنَاكَ شَاهِدًا وَمُبَشِّرًا وَنَذِيرًا وَدَاعِيًا إِلَى اللهِ بِإِذْنِهِ وَسِرَاجًا مُنِيرًا} [الأحزاب 46] {وَأُوحِيَ إِلِيَّ هَذَا الْقُرْآنُ لِأُنْذِرَكُمْ بِهِ وَمَنْ بَلَغَ أَئِنَّكُمْ لَتَشْهَدُونَ أَنَّ مَعَ اللهِ آلِهَةً أُخْرَى} [الأنعام 19] إِلَى آخِرِ الْآيَةِ رَوْحُ بْنُ مُسَافِرٍ ضَعِيفٌ