In the vaccination debate, I’ve heard Romans 14 referenced in different ways. I think it might be helpful to review how Romans 14 properly applies to this and many other differences of opinion between Christians.
As for the one who is weak in faith, welcome him, but not to quarrel over opinions.
Romans 14:1
At issue was whether certain food was off-limits to Christians, specifically, meat offered to pagan idols and then sold in the market (see the parallel treatment in 1 Corinthians 8). Some Christians feared that food offered to idols was spiritually tainted.
Paul made it abundantly clear that the “no-eat” party was wrong (Romans 14:14; 1 Corinthians 8:1-7). Their consciences were held captive by a misunderstanding. They acted as if man-made gods exist, when they actually do not. He called them “weaker” brothers, because their faith was sincerely bound to false ideas. (Note that Paul was not afraid to correct such misunderstandings; some of those “weaker brothers” would be reading his letter.)
If we walked away from the text at this point, then both sides of any Christian debate would characterize the other side as “weaker,” and urge them to cast aside their foolishness and do what is right. But that is not where Paul takes this.
Paul’s point is that when Christians, under pressure from other Christians, do something which they still believe is wrong, then they automatically commit sin (Romans 14:20-23). This is true even when what they do is perfectly fine according to God. The Lord sees the heart, and if I am willing to do what I think is displeasing to him, then I sin, even when what I do is not, in itself, sinful at all. Eating meat offered in an idol’s temple is definitely not sinful. But if I press a brother or sister to eat it while they still believe that it is sinful, then I have caused them to sin. Therefore, we shouldn’t press each other in such matters. Period.
Vaccines, mask wearing and the like are matters of public health, so the State will weigh in. But Christians will discuss these and many other issues among ourselves – matters which are not directly addressed in Scripture, but must be deduced from Scripture. There is an answer. But on one or both sides of an issue there may be Christians whose faith is sincerely bound by misunderstandings. These things are too important to ignore, but trouble comes when one side presses the other to give in and do what they still believe is wrong.
Instead of such quarreling, we are told to gently and patiently help each other mature in the truth, thus freeing our consciences from falsehood and allowing us to discover together what pleases God.
And the Lord’s servant must not be quarrelsome but kind to everyone, able to teach, patiently enduring evil, correcting his opponents with gentleness. God may perhaps grant them repentance leading to a knowledge of the truth.
2 Timothy 2:24-25