The Messenger of Allah ﷺ said, "When a man comes to visit a sick person, let him say, 'O Allah, heal Your servant, that he may strike down an enemy for You, or walk to a funeral for You.'"
قال رسول الله ﷺ: إذا جاء الرجل يعود مريضا فليقل: اللهم اشف عبدك ينكأ لك عدوا، أو يمشي لك إلى جنازة.
Abu Dawud (3107) narrated it from Yazid bin Khalid Ramli, who said, Ibn Wahb narrated to us, from Huyayy bin Abdullah, from Abu Abdul-Rahman Hubli, from Abdullah bin Amr bin As, and he mentioned it.Ibn Hibban (2974) and Hakim (1/344, 549) both graded it sahih, both from the route of Ibn Wahb with similar wording, except that they said, "or walks for you to prayer." Its chain is hasan because of Huyayy bin Abdullah, for his hadith is hasan as long as he does not bring something objectionable.The hadith has other chains, and the one I have mentioned is the soundest of them.As for his saying, "yanka," it means that wounding and killing become widespread among them.