Abu Sa'eed Al-Khudri narrated that:
The Messenger of Allah said: "People will come to you seeking knowledge. When you see them say to them, 'Welcome, welcome,' in obedience to the injunctions of the Messenger of Allah and instruct them in knowledge."(One of the narrators said) "I said to Al-Hakam: 'What is 'Iqnuhum?' He said: 'Instruct them.'"

حَدَّثَنَا مُحَمَّدُ بْنُ الْحَارِثِ بْنِ رَاشِدٍ الْمِصْرِيُّ، حَدَّثَنَا الْحَكَمُ بْنُ عَبْدَةَ، عَنْ أَبِي هَارُونَ الْعَبْدِيِّ، عَنْ أَبِي سَعِيدٍ الْخُدْرِيِّ، عَنْ رَسُولِ اللَّهِ ـ ﷺ ـ قَالَ " سَيَأْتِيكُمْ أَقْوَامٌ يَطْلُبُونَ الْعِلْمَ فَإِذَا رَأَيْتُمُوهُمْ فَقُولُوا لَهُمْ مَرْحَبًا مَرْحَبًا بِوَصِيَّةِ رَسُولِ اللَّهِ ـ ﷺ ـ وَاقْنُوهُمْ " . قُلْتُ لِلْحَكَمِ مَا اقْنُوهُمْ قَالَ عَلِّمُوهُمْ .