Muwatta Imam Malik Book of Suckling, Hadith 14

Yahya related to me from Malik from Yahya ibn Said that a man said to Abu Musa al-Ashari, "I drank some milk from my wife's breasts and it went into my stomach." Abu Musa said, "I can only but think that she is haram for you." Abdullah ibn Masud said, "Look at what opinion you are giving the man." Abu Musa said, "Then what do you say?" Abdullah ibn Masud said, "There is only kinship by suckling in the first two years."
Abu Musa said, "Do not ask me about anything while this learned man is among you."

وَحَدَّثَنِي عَنْ مَالِكٍ، عَنْ يَحْيَى بْنِ سَعِيدٍ، أَنَّ رَجُلاً، سَأَلَ أَبَا مُوسَى الأَشْعَرِيَّ فَقَالَ إِنِّي مَصِصْتُ عَنِ امْرَأَتِي، مِنْ ثَدْيِهَا لَبَنًا فَذَهَبَ فِي بَطْنِي فَقَالَ أَبُو مُوسَى لاَ أُرَاهَا إِلاَّ قَدْ حَرُمَتْ عَلَيْكَ . فَقَالَ عَبْدُ اللَّهِ بْنُ مَسْعُودٍ انْظُرْ مَاذَا تُفْتِي بِهِ الرَّجُلَ فَقَالَ أَبُو مُوسَى فَمَاذَا تَقُولُ أَنْتَ فَقَالَ عَبْدُ اللَّهِ بْنُ مَسْعُودٍ لاَ رَضَاعَةَ إِلاَّ مَا كَانَ فِي الْحَوْلَيْنِ . فَقَالَ أَبُو مُوسَى لاَ تَسْأَلُونِي عَنْ شَىْءٍ مَا كَانَ هَذَا الْحَبْرُ بَيْنَ أَظْهُرِكُمْ .