Allah(swt) says in the Holy Quran:

"And we made a covenant with the children of Isreal: You shall not serve any but Allah and you shall do good to your parents, and to the near kin and to orphans and the needy....." (Quran 2:83)

"....And give away wealth out of love for Him to the near of kin and the orphans and the needy....." (Quran 2:177)

"On this world and the hereafter. And they ask you concerning the orphans say: To set right for them their affairs is good, and if you becom co-partners with them, they are your brethren; and Allah knows the mischief-maker an the peace-maker; and if Allah had pleased, he would certainly have caused you to fall into a difficulty; surely Allah is mighty, wise" (Quran 2:220)

"And give to the orphans their property, and do not subsitute worthless things fortheir good ones, and do not devour their property as an addition to your own property; this is surely a great crime" (Quran 4:2)

"Nay! But you do not honor the orphan, nor do you urge one another to feed the poor"(Quran 89:17-18)

"Therefore, as for the orphan, do not oppress him. And as for him who asks, do not chide him" (93:9-10)

A man once came to our holy prophet Muhammad(pbuh) and told him that he was cold hearted man. The Prophet said if you want your heart to be soft and if you want to reach your needs, do these things: have mercy on the orphan, wipe his head, and feed him from your own food. Your heart will be soft and you will get what you want.

The Holy Prophet Muhammad(pbuh) said:

"Act with an orphan as a merciful father"

"Me the sponsorer of an orphan are in the hevean, if he fears Allah(swt), like this (and he pointed his index finger and middle and opened them apart)"

Imam Jafar Alsadiq (as) said:

"He whom wants to be under Allahs mercy and enter His hevean must improve his morals,be just in judging himself,  have mercy on the orphan,help the weak, and be humble toward Allah(swt), his creator".

It is said in the hadith from the masoomeen(as): "He whom wipes his palm on the head of an orphan out of love, for every strand of hair, Allah(swt) will reward him a palace in janah bigger than the world and what is in it, and what the soul desires, and what the eye enjoys, and he will be in hevean forever"