What is the authenticity of the the statement that helping people is better than a thousand prayers in the Prophet's Mosque, and what is its evidence?

We have not come across a hadith with this exact wording. However, the encouragement to help people is established in several texts, among them is the hadith narrated by Ibn Umar (marfu‘an): "The most beloved of people to Allah are those who are most beneficial to people. And the most beloved of deeds to Allah is happiness that you bring to a Muslim, or relieving him of a hardship, or paying off a debt for him, or warding off hunger from him. And verily, for me to walk with my brother to fulfill a need is more beloved to me than to seclude myself in this mosque for a month. And whoever restrains his anger, Allah will conceal his faults. And whoever suppresses his rage, Allah will fill his heart with hope on the Day of Resurrection. And whoever walks with his brother to fulfill a need for him until he secures it for him, Allah will make his feet firm on the Day when feet will slip."