What is the ruling on stroking the beard?

There is no harm in stroking the beard, unless it is during prayer, due to the fidgeting and distraction it causes from worship and devotion. The people of knowledge have deemed this reprehensible. Sa'id ibn al-Musayyab saw a man fiddling with his beard during prayer and said: "If the heart of this man were humble, his limbs would also be humble."