It is narrated from Sayyiduna Murrah al-Fihri (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) said: "The one who sponsors an orphan, whether the orphan is his own or someone else's, if he is God-conscious, will be with me in Paradise like this," meaning like the index finger and the middle finger.
Hadith Referenceالمعجم الكبير للطبراني / باب الميم / 17890