Tafsir Ibn Kathir -> Surah An-Nahl -> He selected him, as Allah says :

﴿وَلَقَدْ ءَاتَيْنَآ إِبْرَهِيمَ رُشْدَهُ مِن قَبْلُ وَكُنَّا بِهِ عَـلِمِينَ ﴾

(And before, We indeed gave Ibrahim his integrity, and We were indeed most knowledgeable about him)(21:51). Then Allah says:

﴿وَهَدَاهُ إِلَى صِرَطٍ مُّسْتَقِيمٍ﴾

(and guided him to a straight path.) which means to worship Allah alone, without partners or associate, in the manner that He prescribed and which pleases Him.

﴿وَءاتَيْنَـهُ فِى الْدُّنْيَا حَسَنَةً﴾

(And We gave him good in this world,) meaning, `We granted him all that a believer may require for a good and complete life in this world.'

﴿وَإِنَّهُ فِى الاٌّخِرَةِ لَمِنَ الصَّـلِحِينَ﴾

(and in the Hereafter he shall be of the righteous.) Concerning the Ayah:

﴿وَءاتَيْنَـهُ فِى الْدُّنْيَا حَسَنَةً﴾

(And We gave him good in this world,) Mujahid said: "This means a truthful tongue.''

﴿ثُمَّ أَوْحَيْنَآ إِلَيْكَ أَنِ اتَّبِعْ مِلَّةَ إِبْرَهِيمَ حَنِيفًا﴾

(Then, We have sent the revelation to you: "Follow the religion of Ibrahim (he was a) Hanif. ..) meaning, `because of his perfection, greatness, and the soundness of his Tawhid and his way, We revealed to you, O Seal of the Messengers and Leader of the Prophets ,'

﴿أَنِ اتَّبِعْ مِلَّةَ إِبْرَهِيمَ حَنِيفًا وَمَا كَانَ مِنَ الْمُشْرِكِينَ﴾

(Follow the religion of Ibrahim (he was a) Hanif and he was not of the idolators.) This is like the Ayah in Surat Al-An`am:

﴿قُلْ إِنَّنِى هَدَانِى رَبِّى إِلَى صِرَطٍ مُّسْتَقِيمٍ دِينًا قِيَمًا مِّلَّةَ إِبْرَاهِيمَ حَنِيفًا وَمَا كَانَ مِنَ الْمُشْرِكِينَ ﴾

(Say: "Truly, my Lord has guided me to a straight path, a right religion, the religion of Ibrahim, (he was a) Hanif and he was not of the idolators.'') (6:161). Then Allah rebukes the Jews,

﴿إِنَّمَا جُعِلَ السَّبْتُ عَلَى الَّذِينَ اخْتَلَفُواْ فِيهِ وَإِنَّ رَبَّكَ لَيَحْكُمُ بَيْنَهُمْ يَوْمَ الْقِيَـمَةِ فِيمَا كَانُواْ فِيهِ يَخْتَلِفُونَ ﴾

(124. The Sabbath was only prescribed for those who differed concerning it, and verily, your Lord will judge between them on the Day of Resurrection about what they differed over.)