Someone said that a Jewish marriage and a Noahide marriage are 2 different things. Could you give some Halakhic support? Ethical differences? I suppose the 2 have different missions, obviously, but could you elaborate please?
Rambam in Hilchot Ishut 1:1 writes:
קודם מתן תורה היה אדם פוגע אשה בשוק אם רצה הוא והיא לישא אותה מכניסה לתוך ביתו ובועלה בינו לבין עצמו ותהיה לו לאשה. כיון שנתנה תורה נצטוו ישראל שאם ירצה האיש לישא אשה יקנה אותה תחלה בפני עדים ואח"כ תהיה לו לאשה שנאמר כי יקח איש אשה ובא אליה
Before the Torah was given, when a man would meet a woman in the marketplace and he and she decided to marry, he would bring her home, conduct relations in private and thus make her his wife. Once the Torah was given, the Jews were commanded that when a man desires to marry a woman, he must acquire her as a wife in the presence of witnesses. [Only] after this, does she become his wife. This is [alluded to in Deuteronomy 22:13]: "When a man takes a wife and has relations with her...."