Hadith 9412

وَقَالَ : " تَجِدُونَ مِنْ خَيْرِ النَّاسِ أَشَدَّهُمْ كَرَاهِيَةً لِهَذَا الشَّأْنِ ، حَتَّى يَقَعَ فِيهِ " .
And he said: You will see that the person who showed the most aversion to accepting Islam, after accepting Islam, you will find that very person to be the best among you.
Hadith Reference مسند احمد / مسند المكثرين من الصحابة / 9412
Hadith Grading حکم دارالسلام: حدیث صحیح ، وھذا إسناد قوي ،خ : 3496 ، م : 2526