wedding speech

Our son is marrying a Japanese woman next month and he told my husband that he will be expected to make a speech at the wedding thanking everyone. What exactly will he be thanking them for? For attending the ceremony, for being close to the bride and groom, or for something else? Here in US, usually the father of the bride does this. My husband is a little nervous as he doesn't want to offend anyone or say the wrong things.
Any suggestions and help will be greatly appreciated!

Yes, the father will typically be thanking everyone, on the behalf of the bridegroom, bride, and parents of both sides to everyone else, for attending the ceremony, for being close to the bride and groom, and also for hopefully being supportive to their future and generous to the inexperienced couple who have just begun their new life.

But that's just a typical scenario, and it's up to him to say anything nice to all the guests who have taken their time to gather on that day.

In Japan, either father of the newlywedded couple can make this speech, and I do think that quite often the father of the bride does this. He is certainly free however, to reject this offer and insist that the other father do this for one reason or another. They are just honoring him for his position. Although I'm sure the guests will be delighted to hear a speech from someone who has traveled such a long way, and again it would even be nice to make a speech in the style of your custom.

Btw, most fathers are extremely nervous upon doing this and make terrible mistakes which are generousoly accepted by the audience.