Sahih al-Bukhari Book 65, Hadith 303
The Prophet (ﷺ) said, "There is no believer but I, of all the people, I am the closest to him both in this
world and in the Hereafter. Recite if you wish: 'The Prophet (ﷺ) is closer to the believers than their own
selves.' (33.6) so if a believer (dies) leaves some property then his relatives will inherit that property;
but if he is in debt or he leaves poor children, let those (creditors and children) come to me (that I may
pay the debt and provide for the children), for them I am his sponsor (surely).
The Prophet, said, "Allah said, 'I have prepared for My pious worshipers such things as no eye has ever seen, no ear has ever heard of, and nobody has ever thought of. All that is reserved, besides which, all that you have seen, is nothing." Then he recited:-- 'No soul knows what is kept hidden (in reserve) for them of joy as a reward for what they used to do.' (32.17)
We used not to call Zaid bin Haritha the freed slave of Allah's Messenger (ﷺ) except Zaid bin Muhammad till the Qu'anic Verse was revealed: "Call them (adopted sons) by (the names of) their fathers. That is more than just in the Sight of Allah." (33.5)