Walaqad atayna ibraheema rushdahu min qablu wakunna bihi AAalimeen (surah Anbiya: 51)

Tafseer Tafheem-ul-Quran by Syed Abu-al-A'la Maududi

(21:51) Even before that, We had blessed Abraham with the discretion he displayed, for We knew him well. *53

Wa laqad aatainaaa Ibraaheema rushdahoo min qablu wa kunnaa bihee `aalimeen

*53) The Arabic word (rushd) is very comprehensive and means righteousness as well.
"We had blessed Abraham with discretion;" "The discretion he showed in discriminating between the right and the wrong etc. was not of his own acquirement but had been bestowed on him by Us." AI-Anbiyaa'
"We knew him well": "We knew that he was worthy of Prophethood; therefore We appointed him as such". According to VI:124: " .... Allah knows best whom to entrust with His Mission ...."It contains a subtle answer to the objection raised by the chiefs of the Quraish: "Why has Allah appointed this man (the Holy Prophet) to the office of Prophethood, when he is in no way superior to us?" This objection has been answered, as if to say, "The same objection might even have been raised against Prophet Abraham by his people, but We knew his capabilities. Therefore We selected him for Prophethood."
In this connection, please also see II: 124141, 258-260; VI: 74-84; IX: 114; XI: 69-76; XIV: 35-41; XV: 51-58 and XVI: 120-122 and the E.N's thereof.