Riyad as-Salihin 1510
Ibn 'Umar (May Allah be pleased with them) reported:
I never heard 'Umar (May Allah be pleased with him) relating anything that he conceived it to be so-and-so, but that it proved to be as he had conceived it." [Al-Bukhari] .
وعن ابن عمر رضي الله عنهما قال‏:‏ ما سمعت عمر رضي الله عنه يقول لشيء قط‏:‏ إني لأظنه كذا إلا كان كما يظن‏.‏ ‏(‏‏(‏رواه البخاري‏)‏‏)‏