Is it true that we should not talk about politics or religion with others?

from the old testament

• The Old Testament contains examples of people directly addressing religious and spiritual matters. Nathan confronted King David about his sin and its subsequent national consequences (2 Samuel 12:1–7), while Elijah rebuked King Ahab for injustice and idolatry in Israel (1 Kings 21:17–24). These men of God did not allow politics to stand in the way when moral issues were at stake.
• Regarding religion, Daniel openly worshiped God despite religious objections that led to the decree (Daniel 6:10–13). His friends stood up to false worship, defending their worship of God alone (Daniel 3:16–18). When it comes to confronting false religions, God’s people are not to be timid.

from the new testament

• When it comes to all matters, religion and politics included, believers are to “walk in wisdom toward outsiders, making the best use of the time. Let your speech always be gracious, seasoned with salt, so that you may know how you ought to answer each person” (Colossians 4:5–6; cf. 1 Peter 3:15). Discussing politics or religion must be done graciously such that only the gospel is what offends (1 Corinthians 1:23).
• Jesus' final command for all believers is, “Go therefore and make disciples of all nations, baptizing them in the name of the Father and of the Son and of the Holy Spirit, teaching them to observe all that I have commanded you” (Matthew 28:19–20a). We cannot avoid talking about politics and religion while still obeying this command.
• We do this, however, more than just to obey Jesus but out of love for others, which Jesus described as the second greatest commandment (Matthew 22:39). Paul wrote, “For the love of Christ controls us, because we have concluded this: that one has died for all, therefore all have died; and he died for all, that those who live might no longer live for themselves but for him who for their sake died and was raised” (2 Corinthians 5:14–15).
• Paul was also motivated by his knowledge of God’s coming judgment. He said, “knowing the fear of the Lord, we persuade others” (2 Corinthians 5:11a). Not speaking about politics nor religion means missing opportunities to share the gospel and demonstrating a dangerous apathy towards those we are convinced are currently heading toward eternal destruction.
• Paul was known for discussing Jesus in public forums, including political and religious conversations. Acts 17 is an example.
• All spheres of life, including politics, are under God’s domain. God sets up governments to enforce justice (Romans 13:1–7). Paul tells Timothy that believers are to pray for their leaders (1 Timothy 2:1–2), which means they must be engaged at some level to know how to pray.
• Hesitance to speak of spiritual matters may reveal that we fear man more than we fear God. Paul write,"For am I now seeking the approval of man, or of God? Or am I trying to please man? If I were still trying to please man, I would not be a servant of Christ" (Galatians 1:10).

implications for today

Along with "seating two opinionated people next to each other" and "asking the young adults at the table why they're still single," holiday dinner "don't" lists always say, "don't discuss religion or politics." The reason is easy to see: Bringing up people's visible beliefs (religion or politics) challenges their deeper understanding of the world. Like ripping off a Band-Aid, such challenges hurt. That hurt can lead to hostility.

This is why the world wants us to stick to "polite," superficial talk. But what it really shows is that much of the world doesn’t care about others' eternal salvation. Believers cannot bind ourselves under that “rule” when someone's eternal life is at stake.

We can change how we discuss religion and politics, though. We cannot say, “Jesus loves you,” and then turn around and call someone an idiot for supporting another politician. Instead, we need to show what true love looks like we remain respectful and friendly even on the deepest points of departure.

We also shouldn't think our role is to convert; that's the province of the Holy Spirit. Instead, we're to share the truth, "with gentleness and respect" (1 Peter 3:15). A useful good technique is to ask questions for clarification. That helps you know what they believe, may help them realize the bankruptcy of their worldview, and at the very least gives them some food for thought. We're merely the gardeners; God saves (1 Corinthians 3:6).

That said, we should also use wisdom about timing and whether to press a point or let up until the next conversation. When our goal is God's glory, we won't misstep (1 Corinthians 10:31).