Allah said: “…that they may mention the name of Allah on known days.” (al-Ḥajj 22:28). Ibn ʿUmar and Abū Hurayrah would go out to the market in the ten days saying takbīr, and people would say it with them. (al-Bukhārī). The Prophet ﷺ said to increase tahlīl, takbīr and taḥmīd in these days. (Aḥmad).
العربية: كان ابن عمر وأبو هريرة رضي الله عنهما يخرجان إلى السوق في أيام العشر يُكبّران، ويُكبّر الناس بتكبيرهما. (البخاري). وقال النبيّ ﷺ: «فأكثِروا فيهنّ من التهليل والتكبير والتحميد». (أحمد).
Say “Allāhu Akbar, Allāhu Akbar, lā ilāha illa-llāh…” often throughout the ten days of Dhul‑Ḥijjah.