Today's reading is Deuteronomy 5-7 (read it in the KJV or NIV)
Today's passage covers a recap of the ten commandments; the commandment to love God; and the commands Israel will use when conquering the nations living in Canaan.
Shema Israel, Adonai elohanu, Adonai ehad. These are the beginning of what many people consider the most important prayer in Judaism, appropriately called the Shema ("hear"). Observant Jews recite this prayer twice daily. The first parts of the Shema are found in today's readings, Deut. 6:4-9. (The rest of the Shema is Deut. 11:13-21 and Num. 15:37-41.) Let us therefore take a moment to consider these verses as well as the ones that come after it in the rest of Deut. 6.
Deut. 6:4 reads, in the KJV, "Hear, O Israel: The LORD our God is one LORD," but is more commonly translated (here, for instance) as "Hear, Israel, the Lord is our God, the Lord is One." This second translation better reflects the parallelism in the Hebrew. Regardless of which translation you use, the meaning is clear: the Israelites are a monotheistic people, worshipping only one God. One of the major difficulties in early Christian theology, in fact, was reconciling this verse with Trinitarianism, the idea of God the Father, God the Son (Jesus), and God the Holy Spirit. For Jews (and later for Muslims), this is a moot point: there is only one God.
Verse 5 reads, "And thou shalt love the LORD thy God with all thine heart, and with all thy soul, and with all thy might." This threefold repetition is both beautiful and useful: it shows that it is not enough to love God with only one part of the body. Intellectual love is useless without emotional love, and both are worthless without action that reflects them. To me, this is the essential meaning of this passage. The text commands the Israelites to love God all three ways: with the mind, the emotions, and with actions.
Verses 6 to 9 give concrete commands for the Israelites, all of them applying to "these words," in the narrow sense meaning these particular verses but in the wider sense meaning the Bible as a whole. Among the commands are to teach them to your children, talk to them at home and outside, morning and evening, to bind them on your hand and between your eyes, and to write them on the doorposts and gates of your home. Even today, Jews do these things, which has led rise to traditions some gentiles consider strange, such as the teffilin (phylacteries) Jewish men wear on their foreheads and around their arms during prayer, and the mezuzah (pl. mezuzot) affixed to the front doorway in many Jewish homes.
More generally, however, these verses together inform the Israelites that they must be thinking about "these words" all the time. Though the letter of the law states, for example, to speak them morning and evening (Deut. 6:7), this does not mean they can forget about them for the rest of the day. Instead, the phrasing of these verses indicate that the Israelites, and their Jewish descendants, must constantly be thinking and reflecting on the Bible as they go about their daily business. Furthermore, they must teach their children to think in a similar way.
The rest of Deut. 6 is not part of the Shema but continues in this theme. Verses 10-12 remind the Israelites that once they enter Canaan and possess the land, they must not forget God. In fact, even the act of possessing the land will be God's work, as the Israelites will have cities they did not build, houses full of goods they did not fill, wells they did not dig, vineyards and olive trees they did not plant, and so on. In other words, God is about to give them the possessions of other nations for their own, and he pre-emptively warns them not to become decadent and forget the source of all their newfound bounty.
Verses 13-16 further this idea, telling the Israelites not to worship other gods, because God is jealous. The text reminds them that they already tempted God once, at Massah (a reference to Ex. 17). In fact, the Israelites had already tempted God quite a bit, as we saw in the closing essay for Numbers. God is therefore admonishing the Israelites to keep the commandments and therefore be able to live well.
The end of the chapter, verses 20-25, deal with the inevitable question, "why?" Why do we have all these commandments? Why do we have to follow them? The answer, an Israelite father should say to his child, is that we were slaves in Egypt, and God brought us out with signs and wonders, and brought us to Canaan. This same God, who did all these great and wonderful things, commanded us to keep these laws, and therefore we're going to keep them. He was not only good to us, but terrible to our enemies, and we don't want to make him mad.
In short, then, this chapter is a reminder for the Israelites about to enter a new land that they must not forget their benefactor. God knew that the Israelites had a short attention span and were liable to lapse into idolatry and foreign religions, which in fact they eventually did. God sets forth this verse to stave off the rebellion and to ensure the Israelites remember who brought them to Canaan in the first place.