Charge her by an oath, to answer truly to his question, or to declare by oath whether she be guilty or no, and after such oath shall say as follows. If no man, to wit, except thy husband, as is manifest from the whole context; or no other man, the word another being understood here, as it is thought to be also Genesis 14:1, Genesis 36:6 Exodus 22:20. With another, or, with him, i.e. the man now mentioned. So it is an ellipsis easily supplied out of the text.
Related Commentaries of Numbers 5:19
Numbers 5:19
19 And the priest shall charge her by an oath, and say unto the woman, If no man have lain with thee, and if thou hast not gone aside to uncleanness with another instead of thy husband, be thou free from this bitter water that causeth the curse: