"On the occasion of his wedding" 可以用来描述某人在结婚的时候。

这个表达来源于英语中 "occasion" 这个词，其中 "occasion" 意思是 "特殊的时刻、时机、场合"。

例句：

On the occasion of his wedding, John and his bride exchanged vows in front of their famipes and friends. (在他结婚的时候，约翰和他的新娘在他们的家人和朋友面前交换了誓言。)
We were honored to be invited to the wedding on the occasion of their marriage. (我们很荣幸被邀请参加他们结婚的婚礼。)
On the occasion of her wedding, Sarah wore a beautiful white dress. (在她结婚的时候，莎拉穿了一件美丽的白色连衣裙。)