The "skia" in Colossians 2:16 -- to be short and sweet -- is The Lord's Supper, "SABBATHS". 
Take that, if you can, and learn about the following,
'gourmet', Collins, 'of uncertain origin' ---really?  
Not via the KJV  from the Greek?
My Afrikaans Bible omits altogether any idea contained in verse 19, "Nourishment being ministered".
The component words making up the Greek term 'epichorehgoumenon' are recognisable in the English, e.g., a 'gourmet meal'. In context of Colossians 2:16-19, “The Lord’s Supper”.
Follet's Greek Dictionary mentions Horace's 'canis a corio nunquam absterrebitur uncto' from the Doric proverb, 'tis bad to let the dog TASTE LEATHER' ['eat for FOOD, leather' GE] -- 'chalepon CHORIOH kuna geusai'. 
'Chorion’, 'embrionic sac' like an egg filled with food or 'supply'.
‘Chortádzoh’ – ‘fatten’
‘Choreúoh’ – ‘to feast in honour of the gods’
‘Chórtos’ – ‘eating place’
‘Chorós’ – ‘ring’ – ‘gathering’
'Choreography' from the 'choréhgos' – some rich person / ‘chorón dédohka’ – ‘leader’ / ‘chorodidáskalos’ – ‘teacher’ – who paid for FOOD and other needs of ‘the train or band’ of dancers. Everybody had to dance to the ‘choréhgos’ step and sing to his tune – hence, ‘chorus’. 
In Colossians 2:19 Christ is 
“the Head ['choréhgos', ‘Supplier’] 
“from whom supplement / gourmet / food / substance [‘epichoregóúmenon’] 
“is being supplied / fed to the Body the Church [‘chorus’]”. 
“by joints and bands [‘haphóhn kai sundésmohn’ // ‘chordáí’ – ‘chords’ binding together] 
In Colossians 2, verses 16,17 and 18,19 pair in the chiasm, AB-AB 
A: “Do not let judge you anyone in eating and drinking of Christ the SUBSTANCE” 
B: “Spectre of things coming” [16-17]
A: “Do not let beguile you anyone of your REWARD (Christ the) NOURISHMENT being ministered”
B: “Will grow The Body with the growth of God” [18-19]