Why was a sum of money goods and property were also expected at marriage

The money and goods involved in a marriage are called dowry. The basic purpose of a dowry has been to bring some protection for the wife against violence and abuse by her husband and his family. Also, the dowry may serve to help the new couple to establish a home. This was more common in societies where the marriage of very young people has been arranged. Also, a dowry provides the wife with the resources in case of her man's death.

In the Middle Ages, the dowry had the function to enhance the value of a woman for marriage and increase power and wealth of great families. Dowries virtually disappeared in Europe in the XIX and XX century.

must repent and believe in god.

or the book

journey across time - chapter 10 "the rise of christianity"