Musnad Abu Ya'la al-Mawsili 238:11

Abu al-Harith Surayj ibn Yunus narrated to us, Yahya ibn Sa'id narrated to us, from Ibn Jurayj, from 'Asim ibn 'Ubayd Allah, from 'Abd Allah ibn 'Amir ibn Rabi'ah, from his father, who said: The Messenger of Allah (peace and blessings of Allah be upon him) said: "There will be over you leaders who will pray the prayer at its time and will delay it from its time. So, as for when they pray it at its time and you pray it with them, it is for you and for them. And as for when they delay it from its time and you pray it with them, it is for you and against them. And whoever separates from the community has removed the yoke of Islam from his neck. And whoever dies while breaking the covenant will come on the Day of Resurrection having no argument."