Gone aside ... - literally, "gone astray from" thy husband by uncleanness; compare Hosea 4:12.

And the priest shall charge her by an oath,.... Or give her her oath:

and say unto the woman, if no man hath lain with thee: besides her husband:

and thou hast not gone aside to uncleanness with another instead of thy husband; which is but another phrase expressive of the same thing, the sin of adultery:

be thou free from this bitter water that causeth the curse; if this is the case, it shall produce no bitter effects, or bring any curse upon thee.

The oath which the priest required her to take is called, in Numbers 5:21, האלה שׁבעת, "oath of cursing" (see Genesis 26:28); but it first of all presupposes the possibility of the woman being innocent, and contains the assurance, that in that case the curse-water would do her no harm. "If no (other) man has lain with thee, and thou hast not gone aside to union (טמאה, accus. of more precise definition, as in Leviticus 15:2, Leviticus 15:18), under thy husband," i.e., as a wife subject to thy husband (Ezekiel 23:5; Hosea 4:12), "then remain free from the water of bitterness, this curse-bringing," i.e., from the effects of this curse-water. The imperative is a sign of certain assurance (see Genesis 12:2; Genesis 20:7; cf. Ges. 130, 1). "But if thou hast gone aside under thy husband, if thou hast defiled thyself, and a man has given thee his seed beside thy husband,"...(the priest shall proceed to say; this is the meaning of the repetition of לאשּׁה...והשׁבּיע, Numbers 5:21), "Jehovah shall make thee a curse and an oath among thy people, by making thy hip to fall and thy belly to swell; and this curse-bringing water shall come into thy bowels, to make the belly to vanish and the hip to fall." To this oath that was spoken before her the woman was to reply, "true, true," or "truly, truly," and thus confirm it as taken by herself (cf. Deuteronomy 27:15.; Nehemiah 5:13). It cannot be determined with any certainty what was the nature of the disease threatened in this curse. Michaelis supposes it to be dropsy of the ovary (hydrops ovarii), in which a tumour is formed in the place of the ovarium, which may even swell so as to contain 100 lbs. of fluid, and with which the patient becomes dreadfully emaciated. Josephus says it is ordinary dropsy (hydrops ascites: Ant. iii. 11, 6). At any rate, the idea of the curse is this: Δι ̓ ὧν γὰρ ἡ ἁμαρτία, διὰ τούτων ἡ τιμωρία ("the punishment shall come from the same source as the sin," Theodoret). The punishment was to answer exactly to the crime, and to fall upon those bodily organs which had been the instruments of the woman's sin, viz., the organs of child-bearing.

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:

5:19 By an oath - To answer truly to his question, or to declare whether she be guilty or no, and after such oath shall say as follows.

with another...: or, being in the power of thy husband: Heb. under thy husband

5:11-31 This law would make the women of Israel watch against giving cause for suspicion. On the other hand, it would hinder the cruel treatment such suspicions might occasion. It would also hinder the guilty from escaping, and the innocent from coming under just suspicion. When no proof could be brought, the wife was called on to make this solemn appeal to a heart-searching God. No woman, if she were guilty, could say Amen to the adjuration, and drink the water after it, unless she disbelieved the truth of God, or defied his justice. The water is called the bitter water, because it caused the curse. Thus sin is called an evil and a bitter thing. Let all that meddle with forbidden pleasures, know that they will be bitterness in the latter end. From the whole learn, 1. Secret sins are known to God, and sometimes are strangely brought to light in this life; and that there is a day coming when God will, by Christ, judge the secrets of men according to the gospel, Ro 2:16. 2 In particular, Whoremongers and adulterers God will surely judge. Though we have not now the waters of jealousy, yet we have God's word, which ought to be as great a terror. Sensual lusts will end in bitterness. 3. God will manifest the innocency of the innocent. The same providence is for good to some, and for hurt to others. And it will answer the purposes which God intends.