Acts 20:31

So, be very watchful, and remember that for three years I never stopped warning every one of you [about such matters] both night and day with tears [in my eyes].

Matthew 24:24-25

For false Christs and false prophets will appear and they will perform great [miraculous] signs and [supernatural] wonders in order to lead astray even the elect [i.e., God's people], if possible.

1 Corinthians 4:14

I am not writing this to shame you but to warn you, as my dearly loved children.

1 Corinthians 10:12

So, the person who thinks he is standing firm [in the faith] should pay attention [to his life], so that he does not fall [away from God].

Galatians 1:6-10

I am astonished that you people are so quickly abandoning God [i.e., by rejecting His truth], who called you [to Himself] through the unearned favor bestowed [on us] by Christ. [You are turning] to a different "gospel,"

Galatians 2:11-13

But when Cephas came to Antioch [of Syria], I confronted him personally [about a matter] for which he deserved to be condemned.

Galatians 5:2-7

Look, I Paul am telling you that, if you revert to [the practice of] circumcision [i.e., the Jewish rite of identity, signifying the responsibility to observe the law of Moses], then Christ's [sacrifice] will be of no value to you.

Ephesians 4:17-21

So, I tell you this, and insist [on it] by [the authority of] the Lord: Do not continue to live with worthless thoughts as [unconverted] Gentiles do.

Ephesians 5:5-6

For you [should] know this for certain: No sexually immoral or [morally] impure person, or greedy person, who is [the same as] an idol worshiper, has any inheritance in the kingdom of Christ and God.

Colossians 1:28

We proclaim Him, warning and teaching every person with all wisdom, so that we may present every person [to God] complete in [their fellowship with] Christ.

Colossians 3:5-8

So, put to death [i.e., stop practicing the desires of] your physical bodies [such as] sexual immorality, [moral] impurity, lust, evil desires and greed, which is [in reality] idolatry.

1 Thessalonians 4:6-8

And none of you should violate and exploit his brother [or sister] in such a matter. For the Lord will punish people for all these things, just as we told you before and warned you.

1 Thessalonians 5:14

And we urge you, brothers, to warn those who are idle [Note: The word "idle" originally meant, "insubordinate, or unruly." See II Thess. 3:6-7, 11], encourage those who are timid, help the [spiritually] weak and be patient with everyone.

1 Timothy 4:16

Pay close attention to yourself and to what you teach [people]. Continue doing these things, for in doing them you will both save yourself and those who listen to you.

Titus 2:15

You should teach these things and exhort and rebuke people with full authority. Do not let anyone look down on you. [See note on I Tim. 4:12].

James 5:20

that person should know that whoever brings a sinner back from the error of his way will save that soul from [spiritual] death and will cover over a large number of sins [i.e., the many sins of that person will become forgiven].

1 John 3:6-9

No person who lives in [fellowship with] Christ will continue living a sinful life; the one who keeps on sinning [however], has not seen Him or known Him [as his personal Savior].

Revelation 3:19

"I rebuke and discipline those I love, so be earnest and repent.

Treasury of Scripture Knowledge

Summary

Nevertheless if thou warn the righteous man, that the righteous sin not, and he doth not sin, he shall surely live, because he is warned; also thou hast delivered thy soul.

Bible References

He shall

Galatians 2:11
But when Cephas came to Antioch [of Syria], I confronted him personally [about a matter] for which he deserved to be condemned.
James 5:20
that person should know that whoever brings a sinner back from the error of his way will save that soul from [spiritual] death and will cover over a large number of sins [i.e., the many sins of that person will become forgiven].

Also

1 Timothy 4:16
Pay close attention to yourself and to what you teach [people]. Continue doing these things, for in doing them you will both save yourself and those who listen to you.