Rom 14:5, 6 is best translated by one of the very literal version because of its quintessential Pauline terseness. Here is my very literal translation:
One truly judges/esteems a day above a day; but one judges every day
[alike?]. Let each be convinced in mind. The one regarding
the day regards [it] to the Lord; The [one] eating to the Lord eats
for he give thanks to God; and the one not eating, does not eat to the
Lord and gives thanks to God.
Phrases like, "more sacred" & "more holy" are not explicit in the Greek but are strongly implied and thus added by the likes of NIV, NLT, CSB, etc.
B. Distinction: Legalism vs Devotion
At first blush, there appears to be a direct contradiction between Rom 14:5, 6 vs Gal 3 & 4, especially Gal 4:10, "You are observing special days and months and seasons and years!" How are we to resolve this?
Note the repeated use of "to the Lord" and "to God" in Rom 14:5, 6; these phrases are completely absent in Gal 4:8-11.
The commentators, historically, have offered a range of interpretations for this passage in Rom 14:5, 6. This can be summarizes as:
- Paul is alluding to people keeping the Torah-law with its annual Sabbaths and weekly Sabbath and encouraging others to do so. Thus, Paul is talking to "judaeizers". If this is true then we really do have a contradiction between Rom 14 and Gal 4 when Paul outright condemns such judaeizers.
- Paul is talking to two different groups, those brought up in Torah-law and gentiles who were not. He then asks each group to be tolerant of each other, so long as they observe these days out of reverence to God.
- Paul is talking to various groups who were observing various pagan festivals (out of habit). Such practices have come into the modern church with all its "saints days", etc. The modern church has numerous annual "feasts" celebrating various things including Christmas itself(!!) which has no origin in the NT. Different parts of the church have different dates for Christmas and different dates for Easter. Paul is asking these various groups to be tolerant of each other.
Whatever we make of Rom 14, we must make the same assessment of the food and dietary practices as well, which are mentioned in the same light.
Which is correct? Paul correctly condemns legalism in its numerous and subtle forms whether it involves doing works of the law by observing days or eating special food - we cannot earn God favor because we already have it!!
CAUTION - we must be very careful here; some condemn other Christians for observing things by accusing them of legalism - however, all Christian traditions have practices that can become legalistic, including communion, squabbles over communion ritual, baptism and its associated rituals, church attendance, abstinence from alcohol (or not), abstinence from drug abuse, etc.
The two passages in Rom 14 and Gal 4 must be held in tension - if a person does something (no matter how noble) to gain favor with God then it is legalism and should be condemned. However, if a person does something out of devotion to God, perhaps even from a misplaced or immature piety, then it should not be condemned.