You have heard that it was said by them of old time, You shall not commit adultery:
Thou.
Exodus 20:14 Thou shalt not commit adultery.
Leviticus 20:10 And the man that committeth adultery with another man's wife, even he that committeth adultery with his neighbour's wife, the adulterer and the adulteress shall surely be put to death.
Deuteronomy 5:18 Neither shalt thou commit adultery.
‘Do not commit adultery.’
This commandment is the seventh of the Ten Commandments found in Exodus 20:14 and Deuteronomy 5:18. Adultery, in the biblical context, refers to a married person engaging in sexual relations with someone other than their spouse. In ancient Israel, adultery was considered a serious offense, not only against the spouse but also against God, as it violated the covenantal relationship. The prohibition against adultery was intended to protect the sanctity of marriage and the family unit, which were foundational to the social and religious life of Israel. In the broader biblical narrative, adultery is often used metaphorically to describe Israel's unfaithfulness to God, as seen in the prophetic books like Hosea. Jesus, in this passage, is about to expand the understanding of this commandment beyond the physical act to include the intentions and desires of the heart, emphasizing the internalization of God's Law.
Jesus begins by reminding His listeners that they already know the commandment.
• He addresses people familiar with the Law given through Moses (Exodus 20:14; Deuteronomy 5:18).
• By saying “You have heard,” He connects to centuries of synagogue teaching, showing continuity with God’s earlier revelation (Psalm 19:7).
• Jesus affirms the unchanging moral foundation of Scripture while preparing to deepen its application (Malachi 3:6; Matthew 5:17).
The phrase points to an authoritative word from God Himself, not mere human tradition.
• Jesus treats the command as divinely spoken, underscoring the reliability of every word (Psalm 119:89; Matthew 4:4).
• He signals that the original statement still stands; He is about to clarify, not cancel (Isaiah 40:8; Matthew 24:35).
• This approach models how believers today should value and obey the written Word (2 Timothy 3:16).
The seventh commandment prohibits sexual intimacy outside the covenant of marriage.
• It safeguards the exclusivity and sanctity of the one-flesh union established in Genesis 2:24 (cf. Hebrews 13:4).
• Adultery violates a spouse, fractures families, and dishonors God, who is faithful in all His covenants (Hosea 3:1; James 4:4).
• Obedience brings blessing, while disobedience invites judgment—illustrated by David’s experience with Bathsheba (2 Samuel 11–12; Proverbs 6:32-33).
• Jesus will go on (v. 28) to expose the heart-level lust that precedes the physical act, showing that purity is an inner as well as outer call (Job 31:1; 1 Thessalonians 4:3-5).
Matthew 5:27 recalls God’s timeless command, “Do not commit adultery,” confirming its continuing authority. Jesus affirms what the Law says and prepares to reveal its deeper reach into thoughts and desires. The verse reminds us that God values marital faithfulness, protects relationships, and calls His people to mirror His own covenant loyalty in both action and attitude.
(27) By them of old time.--Omitted in the best MSS. If retained, translate as before, to them of old time. It was probably inserted for the sake of conformity with Matthew 5:21. Here the words are simply those of the divine commandment, but it is given as it was taught in the Rabbinic schools, simply in the narrowness of the letter, without any perception that here too the commandment was "exceeding broad." It is with that teaching, as before, that our Lord contrasts His own.Verses 27-30. - The seventh commandment. The verses occur in this form only here, but vers. 29 and 30 are found in Matthew 18:8, 9 (parallel passage, Mark 9:43-47), as illustrations of another subject (vide infra). Verse 27. - By them of old time. Omit, with the Revised Version (cf. ver. 21, note). Thou shalt not (Exodus 20:14; Deuteronomy 5:18).