The Prophet ﷺ said, "Seek out Laylat al-Qadr in the last ten nights."
أن النبي ﷺ قال: التمسوا ليلة القدر في العشر الأواخر.
Imam Ahmad (20809) narrated it from Sulayman bin Dawud, from Sharik, from Simak, from Jabir bin Samura, and he mentioned it. Sharik is Ibn Abdullah the judge, who had poor memory, but he was corroborated. Ibn Abu Shayba (2/513) narrated it from Amr bin Talha, from Asbat bin Nasr, from Simak bin Harb, with his chain of transmission, similarly. Asbat bin Nasr is acceptable for corroboration purposes, and Bukhari said of him, "Truthful." Abdullah bin Ahmad (20930) and Bazzar in Kashf Astar (1031) both narrated it through Abdul-Rahman bin Sharik, who said, my father narrated to me, from Simak, with his chain of transmission, similarly, adding, "in an odd-numbered night, for I had indeed seen it and then forgot it, and it is a night of rain and wind," or he said, "of drizzle and wind." Abdul-Rahman bin Sharik is worse than his father. Abu Hatim said of him, "His hadith is feeble." Nevertheless, Ibn Hibban mentioned him in Thiqat (8/375), though he said of him, "He sometimes erred."Tabarani narrated it in Mujam al-Saghir (285) through another route, from Abu Bakr bin Abu Shayba, who said, I found in my father's book, in his own handwriting, "Shuba narrated to us, from Simak bin Harb, with his chain of transmission," with the wording, "Seek Laylat al-Qadr on the night of the twenty-seventh." Tabarani said, "No one narrated it from Shuba except Muhammad bin Abu Shayba." I say, the father of Abu Bakr bin Abu Shayba is Muhammad bin Ibrahim bin Uthman Absi, their client, the Kufan, and he is "trustworthy." So his being the sole narrator of it does not harm the hadith, given how well known this hadith is from the narration of Shuba, as mentioned previously.