Marriage (Kitab Al-Nikah) hadith Sunan Abu-Dawud

Narrated Jabir ibn Abdullah: The Prophet (peace_be_upon_him) said: When one of you asked a woman in marriage, if he is able to look at what will induce him to marry her, he should do so. He (Jabir) said: I asked a girl in marriage, I used to look at her secretly, until I looked at what induced me to marry her. I, therefore, married her.