Romans 14:5-6 — One man esteemeth one day above another: another esteemeth every day alike. Let every man be fully persuaded in his own mind.
He that regardeth the day, regardeth it unto the Lord; and he that regardeth not the day, to the Lord he doth not regard it. He that eateth, eateth to the Lord, for he giveth God thanks; and he that eateth not, to the Lord he eateth not, and giveth God thanks.
day — Sabbath and other Jewish observances. Let no man therefore judge you in meat, or in drink, or in respect of an holyday, or of the new moon, or of the sabbath days (Colossians 2:16). Ye observe days, and months, and times, and years (Galatians 4:10).
esteemeth every day — consecrates every day to the Lord
and he that regardeth not … not regard it — not in older manuscripts.
Galatians 5:1 — Stand fast therefore in the liberty wherewith Christ hath made us free, and be not entangled again with the yoke of bondage.