Back to the Bible Podcast

Host: Larsen Plyler
Episode 129: Sexual Immorality
Date: October 26, 2025

Episode Overview

In this episode, Larsen Plyler provides a thorough Bible-based examination of sexual immorality, focusing primarily on 1 Thessalonians 4. Through textual analysis, historical context, and cross-referencing, Plyler addresses what scripture teaches regarding sexual conduct, how believers should understand and guard against sexual immorality, and why these teachings are relevant for all, regardless of age or spiritual maturity.

Key Discussion Points & Insights

1. The Universality and Relevance of the Topic

(Starts at 04:54)

• Sexual immorality is a recurring subject throughout the New Testament; nearly every book references it due to its significant spiritual danger.
• Paul's audience in 1 Thessalonians were spiritually mature, faithful Christians, yet he still felt compelled to warn them against sexual immorality.
• The topic is essential for everyone, including young people and children:

  “The world is promoting sexual immorality all around us. …the conversation is happening from a devilish point of view. And so either we completely insulate them, which doesn’t make it better... or we need to have conversations along the way about sexual immorality.” (11:45)

2. Biblical Definition of Sexual Immorality

(Hebrews 13:4, Leviticus 18; starts at 14:42)

• Fornication broadly refers to sexual activity outside the marriage between a husband and wife.

• Adultery is a subset, describing sexual activity where at least one party is already married to someone else.

• Fornication encompasses a variety of illicit acts detailed in Leviticus 18, which Jesus and the apostles referenced as authoritative:

  “When we think about fornication, we are talking about sexual engagement outside of the union between husband and wife… Engagement outside of that qualifies as fornication.” (13:30)

3. Old and New Testament Contexts & Authority

(Acts 15, Leviticus 17-18; starts at 16:30)

• Early church debates (Acts 15) clarified that while many aspects of the Mosaic Law were not binding on Gentile Christians, certain universal moral standards, including prohibitions from Leviticus 17-18 (idolatry, blood, strangled things, and sexual immorality) still applied.

• These prohibitions were not only for Jews—God judged the pagan nations for these same sins (Leviticus 18:24-28).

  “There are some things recorded in the old law that were not just for the Jews… that God held people accountable to of all time, and one of those passages is Leviticus 17-18.” (19:55)

4. New Testament Teachings & Warnings

(1 Corinthians 6, 1 Thessalonians 4; starts at 23:41)

• 1 Corinthians 6:9-11 lists fornication, adultery, homosexuality, and other sins as disqualifying from inheritance in the kingdom of God.

• Paul stresses the need for Christians to “possess his own vessel in sanctification and honor, not in lustful passion like the Gentiles who do not know God.” (1 Thess. 4:4-5)

  “Such were some of you. But you were washed, you were sanctified, you were justified in the name of the Lord Jesus.” (26:27)

5. The Meaning and Limits of ‘Porneia’ / Pornography

(Clarifying modern application; starts at 25:00)

• The Greek word ‘porneia’ (fornication) is the root for ‘pornography.’

• Viewing pornography is a sin, but Plyler clarifies that, biblically, it does not meet the scriptural definition of adultery in the physical/legal sense and therefore does not provide scriptural cause for divorce.

• Jesus’ teachings in Matthew 5 address the inward heart issues—lustful looking is a sin, but it is not equated by Jesus with the act of adultery regarding divorce.

  “Pornography is absolutely a sin. It is absolutely an abomination before God. …But they haven’t committed adultery in the actual terms of fornication and adultery.” (27:50)

6. The Divine Weight of Sexual Purity

(Returns to 1 Thess. 4; starts at 29:13)

• God calls believers to sanctification and holiness as His will for their lives.

• Violating sexual morality is an offense not just against human tradition but directly against God:

  “Whoever sets this aside is not setting aside the man who told you, but God who gives His Holy Spirit to you.” (31:17)

• God’s standard for marriage is strict—divorce is hated by God and only permitted in the case of fornication (Malachi 2:16, Matthew 19:9).

  “That’s how much [God] hates this. …God’s will focuses on abstinence from sexual immorality. His will is for holiness and purity.” (33:51)

Notable Quotes & Memorable Moments

• On teaching children:
  “There are conversations that we need to have, because the conversations are happening whether we have them with them or not.” (11:53)

• On defining sin and consequence:
  “Jesus is trying to address the heart of the matter. …Just because we get the word [pornography] from the same root doesn’t mean that’s what Paul is talking about when he talks about fornication.” (27:44)

• On the seriousness of sexual sin:
  “It’s not just against man’s made up rules. …We are violating God’s instructions. It’s not just against man’s made up traditions. It’s against the will of God from the very beginning.” (32:45)

Key Timestamps

• 04:54 – Introduction to the biblical context of sexual immorality
• 09:30 – Why sexual morality must be taught to all, including children
• 13:30 – Definitions: fornication vs. adultery
• 16:30 – Old Testament background; Leviticus 18
• 19:55 – Application to Gentiles and early church, Acts 15
• 23:41 – 1 Corinthians 6 and the consequences of sexual sin
• 25:00 – ‘Porneia’ and modern questions about pornography
• 29:13 – God’s call to holiness in 1 Thessalonians 4
• 31:17 – Violating God’s standard versus man’s tradition
• 33:51 – God’s hatred of sexual immorality and permissive divorce only for fornication

Conclusion

Larsen Plyler’s teaching in this episode underscores that sexual immorality is a profoundly serious matter with implications for every believer. By grounding the discussion in biblical text, he clarifies the definitions, warnings, and the weight God places on sexual purity, calling listeners to personal holiness above all and reminding them that God’s standard—not societal norms—must be the guide for life and doctrine.