“You.” The “you” is singular from the singular verb. The Hebrew is more literally, “Not will be to you.” The word “must” in our translation comes from the vocabulary and context. The NET (First Edition) text note reads, “The negative with the imperfect [aspect of the verb] expresses the emphatic prohibition; it is best reflected with ‘you will not’ and has the strongest expectation of obedience.”
We felt that the problem with the translation, “you will not,” is that, while it is accurate and in Hebrew expresses an emphatic prohibition, in English it expresses a future prohibition and one that could be confusing because it often turned out not to be factually true, such as when Israel worshipped pagan gods. The problem with the translation “You shall not” or “You shall have no” (ESV; NAB) is that it uses English that is almost never used anymore and can be unclear (years ago the first person use of “shall” referred to a future event while the second person and third person use of “shall” expressed strong determination, but now “shall” is used interchangeably with “will” and can express a prohibition or refer to a future event according to the context, but few people know that). We felt the translation, “Do not have” (HCSB) was good, but did not express the emphatic nature of the Hebrew text, whereas the translation, “You must not have” (NLT) was clear and also captured the emphatic nature of the command. The Ten Commandments are not just “good ideas,” they are God’s emphatic commands.
The impact of the singular instead of the plural in God’s commands cannot be overstated. God was speaking to all of the Israelites: they all heard His voice speaking the Ten Commandments. But God’s commandments were not to the “group;” the singular verbs show us that they were meant to be believed and acted upon individually by each person, and they continue to echo down through the ages in that same way. Each person decides for himself if he will keep God’s commands or ignore or defy them, and each person will stand before the throne on the Day of Judgment and be acquitted or condemned by his obedience or disobedience to God.
It is unfortunate that in English there is no distinction between the second person singular and plural, and thus there is no easy way to tell if “you” means you as an individual or “you all.” An expanded, but somewhat awkward, translation of Exodus 20:3 might be: “Each of you must not have any gods besides me,” or perhaps, “None of you is to have any other God besides me.” That same idea goes for all Ten Commandments. Each of us must honor our parents. Each of us must not murder. Each of us must not steal, and so forth.
In spite of the fact that it is commonly taught that the Ten Commandments were given when God gave them to Moses on stone tablets, that is not what happened. God spoke the Ten Commandments to all Israel in a loud voice off Mount Sinai (Exod. 20:2-17; Deut. 5:4, 20; Heb. 12:19). Moses did not get the stone tablets until much later (Exod. 31:18) and came down the mountain with them even later than that (Exod. 32:15). God’s voice frightened the Israelites, so they requested that Moses speak to God and then tell them what God had said (Exod. 20:18-19).