This is a strategy called double syntax, the notion that "in the Beginning" can modify one verb or the other.

这种手法叫做双关句，也就是,“太初“可同时修饰两个动词。

耶鲁公开课 - 弥尔顿课程节选

Milton needs to imagine the narrative of the Creation as if the narration itself were taking place in the beginning, as if poetic creation could be a first in the same radical way that the creation of entire universe is obviously a first.

弥尔顿想象的对上帝创造万物的讲述,与上帝创造万物一样发生在太初之时，诗歌创作与整个宇宙的创造,都发生在太初之时。

耶鲁公开课 - 弥尔顿课程节选