It is narrated from Sayyiduna Anas bin Malik (may Allah be pleased with him) that Sayyidah Umm Sulaym (may Allah be pleased with her) was with Abu Talhah al-Ansari (may Allah be pleased with him) on the day of Hunayn, and she had a dagger with her. Abu Talhah (may Allah be pleased with him) asked her: "O Umm Sulaym! What is this you have with you?" She said: "I have kept this dagger so that if any of the idolaters comes near me, I will rip open his belly with it." Abu Talhah (may Allah be pleased with him) said: "O Messenger of Allah! Do you not hear what Umm Sulaym is saying? She is saying such and such." I said: "O Messenger of Allah! Those freed ones (tulaqa') who fled and abandoned you have come up behind us, O Messenger of Allah!" He (peace and blessings be upon him) said: "O Umm Sulaym! Allah has sufficed, and has done well."
Hadith Referenceالمعجم الكبير للطبراني / مسند النساء / 21753