It is narrated from Sayyiduna Ibn Umm Maktum (may Allah be pleased with him) that the Prophet (peace and blessings be upon him) came out one morning and said: "The Fire has been kindled, and trials have come like pieces of the dark night. If you knew what I know, you would laugh little and weep much."
This hadith is narrated from Sayyiduna Ibn Umm Maktum (may Allah be pleased with him) only with this chain, and Ishaq bin Sulayman (may Allah have mercy on him) is alone in narrating it.
Hadith Referenceالمعجم الأوسط / باب الألف / 887
Hadith Takhrij«أخرجه الحاكم فى «المستدرك» برقم: 6735، وابن حجر فى «المطالب العالية» برقم: 4343»