His Pure Childhood
Imam Musa made general progress during his childhood. He sucked at the breast of faith and was brought up in the lap of Islam. Imam Abu 'Abd Allah (al-Sadiq), peace be on him, fed him on his sympathy and kindness. He poured down upon him rays of his great soul, guided him to noble habits, and directed him to brilliant behavior. So during his early age all the elements of the Islamic education gathered in him to the extent that during his childhood he attained perfection and education none had ever attained.
Love and Honoring
Imam Musa made good progress during his childhood. He was tranquil and received life with welcome and honoring. Everyday his father showered him with his plentiful sympathy. The Muslim masses met him with care and honoring. Imam al-Sadiq, peace be on him, gave preference to him over the rest of his children; he showed toward him love he did not show toward any other than him. Among the aspects of his love for him is that he gave him a piece of ground called al-Basariya, which he had bought for twenty-six thousand dinars. He was asked about the extent of love for him and he answered: "I wish that I had no child other than him lest none should take part in my love for him."
While still young, Imam Musa said some words that amazed his father, who said: "Praise belongs to Allah Who has made you as a successor instead of the forefathers, a delight in the place of the children, and a substitute for the friends."
The Shi'ites believe that the office of the Imamte is like that of the prophethood irrespective of favoritism, zeal out of the sentiment of love, except confirming virtue and praising faith. Accordingly Imam Abu 'Abd Allah (al-Sadiq), peace be on him, declared his strong love and firm affection for his son. For he came to know that he was a real copy of him in talent and genius. Besides he came to know that he would be the Imam after him over the community of his grandfather.
 Dela'il al-Imama, pp. 49-50.
 Al-Ithaf bi Hub al-Ashraf, p. 54.
 Bihar al-Anwar, vol. 11, p. 237.