Therefore let us not judge one another anymore, but rather resolve this, not to put a stumbling block or a cause to fall in our brother's way. (Romans 14:13)
After reminding Christians that we will all give an account of ourselves to God (Romans 14:12), Paul urges Christians not to cause each other to stumble or fall over these matters of opinion.
Stop judging each other.
The way Paul words the beginning of this sentence - “let us not judge one another anymore” - means this behavior was happening among some of the Christians in Rome.
Romans 14 is not addressing a hypothetical situation, but one currently occurring among the churches of Christ in Rome. Paul is saying, “I know this is happening, and it needs to stop right now.”
The disdain and judgment taking place among the Christians in Rome needed to stop, and a different kind of “judgment” needed to take its place.
Instead, “judge” this: Don’t make your brethren fall.
Paul does a little play on words when he writes “but rather resolve (judge) this…”
What they needed to start doing was resolve not to place a “stumbling block” or a “cause to fall” in their brethren’s path.
A [stumbling block] is something that causes hurt or bruising if one falls over it. Literally, this might involve someone’s falling in the night by tripping over a stone lying in the road. Here it is used figuratively of the inward pain or offense caused by someone’s putting an obstacle, “judging” in this case, in another’s way. In general, a [cause to fall] is a trap for catching something. It can also be used for a “stumbling block.” In other words, Paul warned about harsh criticism and judgmental valuation that might ensnare a fellow believer or cause him to stumble. Judging provokes negative behavior in others, and Paul said this was wrong. - Pollard, Truth for Today Commentary, 506
It is a serious matter to cause a brother to stumble or fall. Because their judgment and disdain over matters of opinion or conscience was placing a stumbling block before their brethren, Paul says, “This needs to stop now.”
When Christians fight over matters of opinion and conscience, we are often blind to the true damage our words and actions inflict upon our brethren and ourselves.
If we truly love the Lord and our brethren, we won’t place a cause to fall in front of our brethren.