Paul winds up the letter with some personal stuff.

mark – skopeo – to look at, observe, contemplate; to mark; to fix one's eyes upon, direct one's attention to. It comes from the word skopos, the goal or end one has in view. Even if you don’t physically have a "goal" in view, your mind is set on the goal.

divisions – dichostasia – dissension, division. Literally, "twice standing". These people are causing people to divide into groups.

offences – skandalon – the movable stick or trigger of a trap, a trap stick; any impediment placed in the way and causing one to stumble or fall, (a stumbling block, occasion of stumbling) i.e. a rock which is a cause of stumbling; any person or thing by which one is (entrapped) drawn into error or sin

doctrine – didache – teaching; that which is taught; doctrin; from didasko – to teach; the thing taught or enjoined; to explain or expound a thing

have learned – manthano – to learn, be appraised; to learn by use and practice; to be in the habit of, accustomed to

avoid – ekklino – to turn aside, deviate (from the right way and course); to turn (one's self) away, to turn away from, keep aloof from one's society; to shun one

serve – douleuo – to be a slave, serve, do service

belly – koilia – the whole belly, the entire cavity; the gullet; to be given up to the pleasures of the palate, to gluttony; the innermost part of a man, the soul, heart as the seat of thought, feeling, choice

good words – chrestologia – fair speaking, the smooth and plausible address which simulates goodness

fair speeches – eulogia – praise; fine discourse, polished language; an invocation of blessing, benediction

deceive – exapatao – to deceive; from apatao – to cheat, beguile, deceive

simple – akakos – without guile or fraud, harmless, free from guilt. Literally, "not evil". NIV has "naïve", NAS has "unsuspecting".

obedience – hupakoe – obedience, compliance, submission; obedience rendered to anyone's counsels, an obedience shown in observing the requirements of Christianity

is come abroad – aphikneomai – to come from a place; to come to, arrive

I am glad – chairo – to rejoice, be glad

wise – sophos – wise; wise, skilled in letters, cultivated, learned

good – agathos – of good constitution or nature; good, pleasant, agreeable, joyful, happy

simple – akeraios – unmixed, pure as in wines or metals; of the mind, without a mixture of evil, free from guile, innocent, simple

evil – kakos – of a bad nature; base, wrong, wicked; troublesome, injurious, pernicious, destructive, baneful

bruise – suntribo – break, to break in pieces, shiver; to tread down; to put Satan under foot and (as a conqueror) trample on him; to break down, crush; to tear one's body and shatter one's strength

Timotheus – Timothy, Paul’s younger disciple. During Paul’s second and third journeys, Timothy would often be sent on short assignments to check up on the churches.

workfellow – sunergos – a companion in work, fellow worker

Tertius was the scribe who wrote while Paul dictated.

Gaius – there was a man named Gaius in the Corinthian church:

chamberlain – Erastus was the city treasurer in Corinth, a prominent man.

is of power – dunamai – to be able, have power whether by virtue of one's own ability and resources, or of a state of mind, or through favourable circumstances, or by permission of law or custom; to be able to do something; to be capable, strong and powerful

to stablish – sterizo ("steroids") – to make stable, place firmly, set fast, fix; to strengthen, make firm; to render constant, confirm, one's mind

was kept secret – sigao – to keep silence, hold one's peace; to be kept in silence, be concealed

made manifest – phaneroo – to make manifest or visible or known what has been hidden or unknown, to manifest, whether by words, or deeds, or in any other way