Deut 6:13 commands fearing and serving God alone, which Deut 13:4 reaffirms as the proper response to the test.

Deuteronomy 10:20 lists 'fear, serve, hold fast'—identical commands to those in Deuteronomy 13:4, reinforcing the same covenantal duties.

Deuteronomy 30:20 sums up the covenant with love, obey, and hold fast, capturing the same core elements as Deuteronomy 13:4.

Deuteronomy 4:4 uses the exact phrase 'held fast to the LORD' and promises life — reinforcing the same call to cling to God.

Deuteronomy 6:2 commands fearing God and keeping commandments — the same core elements of devotion listed in Deuteronomy 13:4.

Deuteronomy 26:16 calls for obedience with all heart and soul — echoing the wholehearted devotion required in Deuteronomy 13:4.

Deuteronomy 26:17 mirrors the language of walking, keeping, and obeying — a direct parallel to the loyalty demanded in Deuteronomy 13:4.

1 Thessalonians 4:1 directly exhorts believers to walk and please God, echoing the Deuteronomy 13:4 call to walk after and obey the Lord.

In 1 Corinthians 6:17, being 'joined to the Lord' parallels the OT call to 'hold fast' to God — a NT application of the same covenantal union.

Luke 1:6 describes Zechariah and Elizabeth walking blamelessly in all commandments, directly mirroring the command to keep commandments and walk after God.

Jeremiah 7:23 repeats the covenant call to obey God's voice and walk in His way, directly paralleling the language of Deuteronomy 13:4.

2 Kings 23:3 records Josiah's covenant to walk after God with all heart, fulfilling the call in Deut 13:4.

In 2 Chronicles 34:31, Josiah's covenant explicitly echoes 'walk after the Lord' and keep commandments, fulfilling the command of Deuteronomy 13:4.

Joshua 23:8 instructs to 'hold fast to the LORD' — the same phrase from Deuteronomy 13:4, urging continued covenant faithfulness.

In 1 Samuel 7:3, Samuel calls Israel to return to the LORD exclusively, echoing the same command to walk after God and serve him only.

Joshua 22:5 repeats nearly verbatim the commands to love, walk, keep, hold fast, and serve — a clear echo of Deuteronomy 13:4.

In Genesis 5:22, Enoch 'walked with God' — a similar expression of faithful devotion, prefiguring the command to walk after the LORD.

Romans 6:13 calls for presenting yourselves to God as instruments of righteousness, a New Testament parallel to serving and holding fast to God in Deuteronomy 13:4.

Colossians 1:10 urges walking worthy of the Lord and pleasing Him, a New Testament application of the 'walk after God' command in Deuteronomy 13:4.

Exodus 23:25 commands serving the LORD with a blessing — directly mirroring the 'serve him' in Deuteronomy 13:4 as an act of covenant loyalty.