Mohammad was twenty-five years old. He was of medium stature; inclined to slimness, with a large head and broad shoulders, and the rest of his body perfectly proportioned. His hair and beard were thick and black, not altogether straight but slightly curled. His hair reached midway between the lobes of his ears and his shoulders, and his beard was of a length to match. He had a noble breadth of forehead and the ovals of his large eyes were wide, with exceptionally long lashes and extensive brows, slightly arched but not joined. In most of the earliest descriptions his eyes are said to have been black, but according to one or two of these they were brown, or even light brown. His nose was aquiline and his mouth was wide and finely shaped-a comeliness always visible for although he let his beard grow, he never allowed the hair of his moustache protrude over his upper lip. His skin was white, but tanned by the sun. In addition to his natural beauty there was a light on his face-the same which had shone from his fater, but in the son it was more powerful-and this light was especially apparent on his broad forehead, and in his eyes, which were remarkably luminous. Khadijah knew that she herself was still beautiful, but she was fifteen years his elder. Would he none the less be prepared to marry her?
She said to him: “Son of mine uncle, I love thee for thy kingship with me, and that for thou art ever in the centre, not being a partisan amongst the people for this or for that, and I love thee for trustworthiness and for the beauty of thy character and for the beauty of thy speech”. Then she offered herself in marriage to him, and they agreed that he should speak to his uncles and she would speak to her uncle `Amr, the son of Asad, for Khuwaylid her father had died.
-Excerpt from Muhammad his life based on the earliest sources by Martin Lings