"The Messenger of Allab passed by a man who was leading another man with something that he had stipulated in a vow. The Prophet took it and broke it, and he said: 'It is a vow.'" (Sahih) Chatper 136. It Is Permissible To Speak During Tawaf
مَرَّ رَسُولُ اللَّهِ ﷺ بِرَجُلٍ يَقُودُهُ رَجُلٌ بِشَىْءٍ ذَكَرَهُ فِي نَذْرٍ فَتَنَاوَلَهُ النَّبِيُّ ﷺ فَقَطَعَهُ قَالَ إِنَّهُ نَذْرٌ