Matthew 5:21 begins the same 'you have heard... but I say' pattern — both are antitheses contrasting OT law with Jesus' demand.

Matthew 23:16 exposes the Pharisees' casuistic oath distinctions, illustrating the kind of legalism Jesus condemns in his oath teaching here.

Exodus 20:7 forbids misusing God's name, which underlies the Old Testament oath command that Jesus builds upon in this verse.

Leviticus 19:12 is the direct source prohibiting false oaths by God's name, which Jesus cites as 'you shall not swear falsely'.

Numbers 30:2 commands fulfilling vows made to the Lord, mirroring the 'perform to the Lord what you have sworn' that Jesus quotes.

Deuteronomy 23:23 insists on carefully performing whatever you vow, directly echoing the 'perform to the Lord' requirement.

Psalm 116:14 illustrates faithful vow-keeping in the OT — paying vows publicly, which the law commanded.

James 5:12 directly echoes Jesus' command not to swear at all — the same 'let your yes be yes' teaching from Matthew 5:37.

Psalm 15:4 commends swearing to one's own hurt and not changing, exemplifying the integrity behind fulfilling vows.

Psalm 50:14 calls for performing vows to the Most High, reinforcing the OT emphasis on keeping sworn promises.

Psalm 76:11 commands making and performing vows to the Lord, matching the same OT principle Jesus quotes.

Psalm 119:106 shows a righteous person swearing to keep God's laws — the kind of oath the OT approved.

Proverbs 20:25 warns against rash vows — the OT background that Jesus' teaching on oaths addresses.

Ecclesiastes 5:4-6 warns against delaying or failing to pay vows, reinforcing the duty to fulfill what is sworn.

Deuteronomy 5:11 bans taking the Lord's name in vain, a broader command underlying the specific oath law Jesus references.

1 Timothy 1:10 lists false swearers among lawbreakers — showing oath-breaking was condemned, the sin Jesus intensifies.