15 So then, brothers and sisters, stand firm and hold fast to the teachings[c] we passed on to you, whether by word of mouth or by letter. 2 Thessalonians 2:15
This verse comes from a very encouraging passage where Paul is talking to the Thessalonians.
13 But we ought always to thank God for you, brothers and sisters loved by the Lord, because God chose you as firstfruits[b] to be saved through the sanctifying work of the Spirit and through belief in the truth. 14 He called you to this through our gospel, that you might share in the glory of our Lord Jesus Christ. 15 So then, brothers and sisters, stand firm and hold fast to the teachings[c] we passed on to you, whether by word of mouth or by letter. 16 May our Lord Jesus Christ himself and God our Father, who loved us and by his grace gave us eternal encouragement and good hope,17 encourage your hearts and strengthen you in every good deed and word.
Honestly I could go through this passage line-by-line and dissect each point, but nothing speaks more clearly than the word of God. This passage is so rich, and it is a reminder for us about who we are and who we are called to be.
I encourage you to read the above a few times, let it sink in and know that this is my prayer for you today (and everyday!)
I have hidden your word in my heart
that I might not sin against you. Psalm 119:11