This verse is a long, complex sentence. The main verb is in the final clause—you shall keep …. Good News Translation helpfully breaks this into two sentences, placing the which clause first.

And when the LORD brings you is literally “And it shall be that Yahweh will cause you to enter.” (The you is singular but understood collectively.) Into the land of refers to one large territory, later known as Palestine. But it was the land that was occupied by several non-Israelite tribes.

The five ethnic groups listed are all named as “-ites.” (A sixth group, the Perizzites, are mentioned in 3.8. See the discussion there.) In languages where this form is not possible, they may have to be referred to as “the people of a place.” The Canaanites will then be “the people of Canaan,” and the Hittites will be “the people of Hatti.” Similarly the Amorites will be “the people of Amurru,” the Hivites “the people of Hor,” and the Jebusites “the people of Jebus.”

Which refers back to the land, and he swore means that Yahweh “promised by oath” (Durham), or “solemnly promised” (Good News Translation). The Hebrew word “to swear” (shavaʿ) comes from the word for the number “seven” (shevaʿ), suggesting the idea of completeness. It meant to take an oath, which involved calling upon the name of a god to make it binding. So Yahweh had to swear by his own self, and in so doing he bound himself to the ancestors Abraham, Isaac, and Jacob. In this context a rendering such as “he made a strong promise,” or even “he promised using his name,” will be helpful. (See also the comment at 32.13.) To your fathers refers back to the patriarchs, so “ancestors” or “forefathers” (Revised English Bible, New International Version) is better. (See “ancestors” and the comment at 3.6.) To give you refers to the descendants of the patriarchs, that is, the Israelites to whom Moses is speaking (see Gen 13.15). (The you and your are still singular but understood collectively.) A land flowing with milk and honey is figurative language for “that rich and fertile land,” as in 3.8 and 17. Good News Translation and Contemporary English Version place the information in this clause at the beginning of the verse. Many translators will wish to follow this restructuring.

You shall keep this service is literally “you [singular] will work this work,” or “serve this service.” It means “you shall keep this observance” (New Revised Standard Version), “observe this rite” (Revised English Bible), “celebrate this festival” (Good News Translation), or “celebrate these events” (Contemporary English Version). This service refers to the seven-day observance described in the following verses, so some translations place a colon at the end of the verse (New Jewish Publication Society’s Tanakh, New International Version, Revised English Bible). In this month means Abib (verse 4), and this implies annually. So Good News Translation has “in the first month of every year.” One may also say “Each year in the month of Abib, celebrate this festival in the following way:….”

Quoted with permission from Osborn, Noel D. and Hatton, Howard A. A Handbook on Exodus. (UBS Helps for Translators). New York: UBS, 1999. For this and other handbooks for translators see here .