Right ( δικαιον ). In Col 3:20 it is  ευαρεστον (well-pleasing).

Which ( ητις ). "Which very" = "for such is."

The first commandment with promise ( εντολη πρωτη εν επαγγελια ).  Εν here means "accompanied by" (Alford). But why "with a promise"? The second has a general promise, but the fifth alone (Ex 20:12) has a specific promise. Perhaps that is the idea. Some take it to be first because in the order of time it was taught first to children, but the addition of  εν επαγγελια here to  πρωτη points to the other view.

That it may be well with thee ( ινα ευ σο γενητα ). From Ex 20:12, "that it may happen to thee well."

And thou mayest live long on the earth ( κα εση μακροχρονιος επ της γης ). Here  εση (second person singular future middle) takes the place of  γενη in the LXX (second person singular second aorist middle subjunctive).  Μακροχρονιος is a late and rare compound adjective, here only in N.T. (from LXX, Ex 20:12).

Provoke not to anger ( μη παροργιζετε ). Rare compound, both N.T. examples (here and Ro 10:19) are quotations from the LXX. The active, as here, has a causative sense. Parallel in sense with  μη ερεθιζετε in Col 3:21. Paul here touches the common sin of fathers.

In the chastening and admonition of the Lord ( εν παιδεια κα νουθεσια του κυριου ).  Εν is the sphere in which it all takes place. There are only three examples in the N.T. of  παιδεια, old Greek for training a  παις (boy or girl) and so for the general education and culture of the child. Both papyri and inscriptions give examples of this original and wider sense (Moulton and Milligan, Vocabulary). It is possible, as Thayer gives it, that this is the meaning here in Eph 6:4. In 2Ti 3:16 adults are included also in the use. In Heb 12:5,7,11 the narrower sense of "chastening" appears which some argue for here. At any rate  νουθεσια (from  νουσ, τιθημ ), common from Aristophanes on, does have the idea of correction. In N.T. only here and 1Co 10:11; Tit 3:10.

With fear and trembling ( μετα φοβου κα τρομου ). This addition to Col 3:22.

But as servants of Christ ( αλλ' ως δουλο Χριστου ). Better "slaves of Christ" as Paul rejoiced to call himself (Php 1:1).

Doing the will of God ( ποιουντες το θελημα του θεου ). Even while slaves of men.

With good will ( μετ' ευνοιας ). Not in Col. Old word from  ευνοος, only here in N.T. as  ευνοεω is in N.T. only in Mt 5:25.

Whatsoever good thing each one doeth ( εκαστος εαν τ ποιηση αγαθον ). Literally, "each one if he do anything good." Condition of third class, undetermined, but with prospect. Note use here of  αγαθον rather than  αδικον (one doing wrong) in Col 3:25. So it is a reward ( κομισετα ) for good, not a penalty for wrong, though both are true, "whether he be bond or free" ( ειτε δουλος ειτε ελευθερος ).

And forbear threatening ( ανιεντες την απειλην ). Present active participle of  ανιημ, old verb, to loosen up, to relax. "Letting up on threatening."  Απειλη is old word for threat, in N.T. only here and Ac 4:29; 9:1.

Both their Master and yours ( κα αυτων κα υμων ο κυριος ). He says to "the lords" ( ο κυριο ) of the slaves. Paul is not afraid of capital nor of labour.

With him ( παρ' αυτω ). "By the side of him (God)."

Finally ( του λοιπου ). Genitive case, "in respect of the rest," like Ga 6:17. D G K L P have the accusative  το λοιπον (as for the rest) like 2Th 3:1; Php 3:1; 4:8.

Be strong in the Lord ( ενδυναμουσθε εν κυριω ). A late word in LXX and N.T. (Ac 9:22; Ro 4:20; Php 4:13), present passive imperative of  ενδυναμοω, from  εν and  δυναμις, to empower. See 1:10 for "in the strength of his might." Not a hendiadys.

Put on ( ενδυσασθε ). Like 3:12. See also 4:24.

The whole armour ( την πανοπλιαν ). Old word from  πανοπλος (wholly armed, from  παν, οπλον ). In N.T. only Lu 11:22; Eph 6:11,13. Complete armour in this period included "shield, sword, lance, helmet, greaves, and breastplate" (Thayer). Our "panoply." Polybius gives this list of Thayer. Paul omits the lance (spear). Our museums preserve specimens of this armour as well as the medieval coat-of-mail. Paul adds girdle and shoes to the list of Polybius, not armour but necessary for the soldier. Certainly Paul could claim knowledge of the Roman soldier's armour, being chained to one for some three years.

That ye may be able to stand ( προς το δυνασθα υμας στηνα ). Purpose clause with  προς το and the infinitive ( δυνασθα ) with the accusative of general reference ( υμας ) and the second aorist active infinitive  στηνα (from  ιστημ ) dependent on  δυνασθα. Against ( προς ). Facing. Another instance of  προς meaning "against" (Col 2:23).

The wiles of the devil ( τας μεθοδιας του διαβολου ). See already 4:14 for this word. He is a crafty foe and knows the weak spots in the Christian's armour.

Our wrestling is not ( ουκ εστιν ημιν η παλη ). "To us the wrestling is not."  Παλη is an old word from  παλλω, to throw, to swing (from Homer to the papyri, though here only in N.T.), a contest between two till one hurls the other down and holds him down ( κατεχω ). Note  προς again (five times) in sense of "against," face to face conflict to the finish.

The world-rulers of this darkness ( τους κοσμοκρατορας του σκοτους τουτου ). This phrase occurs here alone. In Joh 14:30 Satan is called "the ruler of this world" ( ο αρχων του κοσμου τουτου ). In 2Co 4:4 he is termed "the god of this age" ( ο θεος του αιωνος τουτου ). The word  κοσμοκρατωρ is found in the Orphic Hymns of Satan, in Gnostic writings of the devil, in rabbinical writings (transliterated) of the angel of death, in inscriptions of the Emperor Caracalla. These "world-rulers" are limited to "this darkness" here on earth.

The spiritual hosts of wickedness ( τα πνευματικα της πονηριας ). No word for "hosts" in the Greek. Probably simply, "the spiritual things (or elements) of wickedness."  Πονηρια (from  πονηρος ) is depravity (Mt 22:18; 1Co 5:8).

In the heavenly places ( εν τοις επουρανιοις ). Clearly so here. Our "wrestling" is with foes of evil natural and supernatural. We sorely need "the panoply of God" (furnished by God).

Take up ( αναλαβετε ). Second aorist active imperative of  αναλαμβανω, old word and used ( αναλαβων ) of "picking up" Mark in 2Ti 4:11.

That ye may be able to withstand ( ινα δυνηθητε αντιστηνα ). Final clause with  ινα and first aorist passive subjunctive of  δυναμα with  αντιστηνα (second aorist active infinitive of  ανθιστημ, to stand face to face, against).

And having done all to stand ( κα απαντα κατεργασα μενο στηνα ). After the fight (wrestle) is over to stand ( στηνα ) as victor in the contest. Effective aorist here.

Stand therefore ( στητε ουν ). Second aorist active imperative of  ιστημ (intransitive like the others). Ingressive aorist here, "Take your stand therefore" (in view of the arguments made).

Having girded your loins with truth ( περιζωσαμενο την οσφυν υμων εν αληθεια ). First aorist middle participle (antecedent action) of  περιζωννυω, old verb, to gird around, direct middle (gird yourselves) in Lu 12:37; but indirect here with accusative of the thing, "having girded your own loins." So  ενδυσαμενο (having put on) is indirect middle participle.

The breast-plate of righteousness ( τον θωρακα της δικαιοσυνης ). Old word for breast and then for breastplate. Same metaphor of righteousness as breastplate in 1Th 5:8.

Having shod ( υποδησαμενο ). "Having bound under" (sandals). First aorist middle participle of  υποδεω, old word, to bind under (Mr 6:9; Ac 12:8, only other N.T. example).

With the preparation ( εν ετοιμασια ). Late word from  ετοιμαζω, to make ready, only here in N.T. Readiness of mind that comes from the gospel whose message is peace.

Taking up ( αναλαβοντες ). See verse 13.

The shield of faith ( τον θυρεον της πιστεως ). Late word in this sense a large stone against the door in Homer, from  θυρα, door, large and oblong (Latin scutum),  ασπις being smaller and circular, only here in N.T.

To quench ( σβεσα ). First aorist active infinitive of  σβεννυμ, old word, to extinguish (Mt 12:20).

All the fiery darts ( παντα τα βελη τα πεπυρωμενα ).  Βελος is an old word for missile, dart (from  βαλλω, to throw), only here in N.T.  Πεπυρωμενα is perfect passive participle of  πυροω, old verb, to set on fire, from  πυρ (fire). These darts were sometimes ablaze in order to set fire to the enemies' clothing or camp or homes just as the American Indians used to shoot poisoned arrows.

The helmet of salvation ( την περικεφαλαιαν του σωτηριου ). Late word ( περι, κεφαλη, head, around the head), in Polybius, LXX, 1Th 5:8; Eph 6:17 alone in N.T.

Which is the word of God ( ο εστιν το ρημα του θεου ). Explanatory relative ( ο ) referring to the sword ( μαχαιραν ). The sword given by the Spirit to be wielded as offensive weapon (the others defensive) by the Christian is the word of God. See Heb 4:12 where the word of God is called "sharper than any two-edged sword."

At all seasons ( εν παντ καιρω ). "On every occasion." Prayer is needed in this fight. The panoply of God is necessary, but so is prayer.

"Satan trembles when he sees The weakest saint upon his knees."

That utterance may be given unto me ( ινα μο δοθη λογος ). Final clause with  ινα and first aorist passive subjunctive of  διδωμ, to give. See a like request in Col 4:3. Paul wishes their prayer for courage for himself.

For which I am an ambassador in chains ( υπερ ου πρεσβευω εν αλυσε ). "For which mystery" of the gospel (verse 19).  Πρεσβευω is an old word for ambassador (from  πρεσβυς, an old man) in N.T. only here and 2Co 5:20. Paul is now an old man ( πρεσβυτης, Phm 1:9) and feels the dignity of his position as Christ's ambassador though "in a chain" ( εν αλυσε, old word  αλυσις, from  α privative and  λυω, to loosen). Paul will wear a chain at the close of his life in Rome (2Ti 1:16).

In it ( εν αυτω ). In the mystery of the gospel. This is probably a second purpose ( ινα ), the first for utterance ( ινα δοθη ), this for boldness ( ινα παρρησιασωμα, first aorist middle subjunctive, old word to speak out boldly). See 1Th 2:2. See Col 4:4 for "as I ought."

That ye also may know ( ινα ειδητε κα υμεις ). Final clause with  ινα and second perfect subjunctive active of  οιδα. For Tychicus, see Col 4:7f.

That ye may know ( ινα γνωτε ). Second aorist active subjunctive of  γινωσκω. Just as in Col 4:8 he had not written  ινα ειδητε in verse 21.

Our state ( τα περ ημων ). "The things concerning us," practically the same as  τα κατ' εμε of verse 21. See both phrases in Col 4:7,8.

Love and faith ( αγαπη μετα πιστεως ). Love of the brotherhood accompanied by faith in Christ and as an expression of it.

In uncorruptness ( εν αφθαρσια ). A never diminishing love. See 1Co 15:42 for  αφθαρσια.