Sayyiduna Abu Hurayrah (may Allah be pleased with him) reports this saying of the Prophet (peace and blessings be upon him): "A group of my Ummah will continue to fight at the gates of Damascus and around it, and at the gates of Bayt al-Maqdis and around it. Whoever tries to forsake them, his attempt will not harm them (that is, the Muslims), and they will continue to be steadfast upon the truth until the Hour is established."
Abu Ya'la recorded it, and its narrators are thiqat (trustworthy).
Hadith Referenceمجمع الزوائد ومنبع الفوائد / كتاب المناقب / 16662