We can also see in this phrase "in the Beginning" - we can see it applying to the end of the preceding clause, "That Shepherd who first taught the chosen Seed / in the Beginning."

太初“一词“,还修饰了后面跟着的从句，“那个牧羊人，最初向您的选民宣讲“

耶鲁公开课 - 弥尔顿课程节选