2 Thessalonians 2:15

So then, brothers, stand firm and hold fast to the traditions which you were taught, whether by [spoken] word or by letter from us.

1 Corinthians 11:2

Now I praise you that you remember me [in] all [things], and just as I handed over to you the traditions, you hold fast to [them].

1 Corinthians 16:13

Be on the alert, stand firm in the faith, act courageously, be strong.

2 Thessalonians 2:2

that you not be easily shaken from your composure, nor be troubled either by a spirit or by a message or by a letter {alleged to be from us}, to the effect that the day of the Lord has arrived.

2 Thessalonians 3:6

But we command you, brothers, in the name of our Lord Jesus Christ, [that] you keep away from every brother who lives irresponsibly and not according to the tradition that they received from us.

Romans 16:17

Now I exhort you, brothers, to look out for those who cause dissensions and temptations contrary to the teaching which you learned, and stay away from them.

1 Corinthians 15:58

So then, my dear brothers, be steadfast, immovable, always abounding in the work of the Lord, [because you] know that your labor is not [in] vain in the Lord.

Philippians 4:1

So then, my beloved and greatly desired brothers, my joy and crown, thus stand firm in the Lord, dear friends.

2 Thessalonians 3:14

But if anyone does not obey our message through this letter, take note not to associate with him, in order that he may be put to shame.

Jude 1:3

Dear friends, [although I] was making every effort to write to you concerning our common salvation, I considered [it] a necessity to write to you to encourage [you] to contend for the faith delivered once and for all to the saints.

Treasury of Scripture Knowledge

Summary

Therefore, brethren, stand fast, and hold the traditions which ye have been taught, whether by word, or our epistle.

Bible References

Whether

2 Thessalonians 2:2
that you not be easily shaken from your composure, nor be troubled either by a spirit or by a message or by a letter {alleged to be from us}, to the effect that the day of the Lord has arrived.
2 Thessalonians 3:14
But if anyone does not obey our message through this letter, take note not to associate with him, in order that he may be put to shame.