It was narrated from Al-Hakam bin Mina' that:
He heard Ibn Abbas and Ibn Umar narrated that while he was on the minbar, the Messenger of Allah (ﷺ) said: "People should stop negleting jumu'ah or Allah (SWT) will place a seal on their hearts and they will be deemed as being among the negligent." (ES)
App reference (ES): Book 14, Hadith 6 (ES)
English reference (ES): Vol. 2, Book 14, Hadith 1371 (ES)
Arabic reference (ES): Book 14, Hadith 1380 (ES)