Marthad bin Abdullah al-Yazani (may Allah have mercy on him) said: Sayyiduna Abu Ayyub (may Allah be pleased with him) came to us on a military campaign, and Sayyiduna Uqbah bin Amir (may Allah be pleased with him) was in Egypt in those days. He delayed Maghrib, so Sayyiduna Abu Ayyub (may Allah be pleased with him) went up to him and said: "O Uqbah! What prayer is this?" He said: "We were kept busy." Sayyiduna Abu Ayyub (may Allah be pleased with him) said: "By Allah! I would have no regret at all, except that people will think that you saw the Messenger of Allah (peace and blessings be upon him) doing (it this way), and then it will be done this way. I heard the Messenger of Allah (peace and blessings be upon him) say: 'My Ummah will remain upon goodness, or upon the fitrah (natural way), as long as they do not delay Maghrib until the stars appear thickly in the sky.'"
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الصلاة / 1728