When the Messenger of Allah ﷺ swore an oath strongly, he said: No, by Him in Whose hand is the soul of AbulQasim. (Using translation from Abū Dāʾūd 3264)
كَانَ رَسُولُ اللهِ ﷺ إِذَا اجْتَهَدَ فِي الْيَمِينِ قَالَ لَا وَالَّذِي نَفْسُ أَبِي الْقَاسِمِ بِيَدِهِ