Do you know who the weak in the faith are? It is somebody who has not grasped yet what Christianity really means. This person may be quite intelligent. To this person, Christianity may exist only in the world of study and of religious technicalities.
By contrast, the strong Christian is one who sees what is important morally, spiritually, ethically, and is able to discern between what is important and what is not important. He is prepared to do the right thing no matter which way he will go. The weak, on the other hand, are preoccupied with some matters to such an extent that they assume an importance all out of proportion to their real value.
Verse 1 here is telling us not to even force the truth upon others. He simply says receive them. If you will compare Romans 14 with I Corinthians 8 through 10, you will find that the subject matter is virtually identical. A comparison of the two will show you that the apostle Paul theologically was in agreement with the ones who were wrong in what they did. Theologically they were correct, but what they did was unrighteous even though it was based upon their conviction about something that was right. An interesting case indeed. The parties who were doing the offending were the ones who were theologically correct, and Paul said they were sinning.
Put on Christ's way of approaching these things, and if there is a weak member of the faith, receive him. But if he is disputing doubtful things, Paul says leave them at arm's length, not to disputes over doubtful things.