Tense question

I'm having trouble with the tense of this sentence. The narrative its part of is in simple past tense.

"But despite the calm of the living forest, I knew that it was going to be the moon that guided our safe passage that evening. "

Thanks

(sorry about all the threads, but I'm working on a school assignment. )

The present form of this is:
...I know that it is going to be the moon that will guide [us]...

Its alternate, using present "guides" for future "will guide", but with the same meaning:
...I know that it is going to be the moon that guides [us]...

The past forms of the same sentences are:

...I knew that it was going to be the moon that would guide [us]...
...I know that it was going to be the moon that guided [us]...

Does that help?