Ibn Ka'b bin Malik (may Allah have mercy on him) said: It was Abu Lubabah (may Allah be pleased with him), and he mentioned the same meaning. Abu Dawud (may Allah have mercy on him) said: The story is about Abu Lubabah (may Allah be pleased with him).
Al-Shaykh (may Allah have mercy on him) said: It is with this wording in the story of Abu Lubabah; as for what he (peace and blessings be upon him) said to Ka'b bin Malik, it was not fixed at a third.
Hadith Referenceالسنن الكبرى للبيهقي / كتاب الأيمان / 20052