It is narrated from Hazrat Ziyad bin Naeem Hadhrami (may Allah be pleased with him) that the Messenger of Allah (peace and blessings be upon him) said: Allah has made four things obligatory in Islam. If a person acts upon even three of them, he will not benefit from them until he brings all of them together: prayer, zakat, fasting, and Hajj.
Hadith Referenceمسند احمد / مسند الشاميين / 17789
Hadith Gradingحکم دارالسلام:إسناده ضعيف، ابن لهيعة سيئ الحفظ، ثم إن الحديث مرسل، زياد بن نعيم تابعي