Musnad Ahmad 179
It was narrated that Ma'dan bin Abi Talhah said:
'Umar said: I never asked the Messenger of Allah ﷺ about anything more than I asked him about kalalah, until he poked me in the chest with his finger and said: `Is not ayatus-saif (the verse of summer, i.e., it was revealed in summer), which appears at the end of Sooratan-Nisa', sufficient for you?”
حَدَّثَنَا إِسْمَاعِيلُ، عَنْ سَعِيدِ بْنِ أَبِي عَرُوبَةَ، عَنْ قَتَادَةَ، عَنْ سَالِمِ بْنِ أَبِي الْجَعْدِ، عَنْ مَعْدَانَ بْنِ أَبِي طَلْحَةَ، قَالَ قَالَ عُمَرُ رَضِيَ اللَّهُ عَنْهُ مَا سَأَلْتُ رَسُولَ اللَّهِ صَلَّى اللَّهُ عَلَيْهِ وَسَلَّمَ عَنْ شَيْءٍ أَكْثَرَ مِمَّا سَأَلْتُهُ عَنْ الْكَلَالَةِ حَتَّى طَعَنَ بِإِصْبَعِهِ فِي صَدْرِي وَقَالَ تَكْفِيكَ آيَةُ الصَّيْفِ الَّتِي فِي آخِرِ سُورَةِ النِّسَاءِ‏.‏