It is from ancient Chinese.
而 is a function word, 言 is speak. In modern Chinese we have another word "来说". Both of them are frequently used, but 而言 is more formal.就....来说,对....来说。
对.....而言。对大学生而言,小学生的作业实在太容易了。For a collage student, xxxxxxx is so easy.
就.....而言。 就成本而言, 第一个计划较好. In point of cost, the first plan is better.