Certain Biblical paragraphs are stated in a Theme-Development form. In other words a broad general idea is stated first followed by the development of this broad general theme in specific details. The Theme-Detail form creates a unified paragraph. Today's example illustrates this as shown below.

Verse Ex39-32a discussing the completion of the Temple states General: Thus was finished all the work of the tabernacle of the tent of meeting; [since]... Detail: ... the children of Israel did according to all that HaShem commanded Moses, so did they.

In the above translation we have interpolated the word since which captures the essence of Rashi's remark on a causal connection between the two verse halves. This causal relationship exhibits the general-development form: The general idea of completion is developed using the causal idea of obedience.

Advanced Rashi: There is a subtle point here: The Temple, even though it is God's house, was not built by God (compare the Midrash that God will build the 3rd Temple). Man had to participate for the Temple to be built in a timely manner.