The Book of the Believer · Hadith 110 (#Ḥadīth #4)
Chapter 5 | The Reward of Helping a Believer, Relieving Him of Distress And Showing Him Kindness
وعن أبي جعفر عليه السلام قال: من خطا في حاجة أخيه المسلم بخطوة كتب الله له بها عشر حسنات، وكانت له خيرا من [عتق ظ] عشر رقاب، و صيام شهر واعتكافه في المسجد الحرام
110. It has been reported that Abu Ja'far said: One who takes one step in fulfilling the need of his Muslim brother, Allah writes for him ten good deeds and it is better for him than freeing ten slaves, and fasting for a month and performing i'tikaf (isolation for worship) in the Sacred Mosque (of Makkah)
Gradings are classical jarḥ-wa-taʿdīl, name-matched to a rijāl index (not individually re-verified).