Rulings related to fulfilling vows cont.
Ibn 'Umar (may Allah be pleased with him) narrated: That ‘Umar said "O Allah's Apostle! I vowed to perform I'tikaf for one night in Al-Masjid-al-Haram, during the Pre-Islamic Period of ignorance (before embracing Islam). "The Prophet said, "Fulfill your vow." (Bukhaari)
Al-Bara (may Allah be pleased with him) narrated: That the Prophet ordered us to help others to fulfill the vows/oaths. (Bukhaari)
(2) If one makes a vow before becoming a Muslim, he must still fulfil this vow.
A vow is like having a debt over your head, 
and it will be with you until you fulfil it!!