2 Like a fluttering sparrow or a darting swallow,
an undeserved curse does not come to rest.
I had some trouble getting my head around this one, for I was looking at it a little bit sideways . . . I was thinking that even if it is undeserved, a malicious comment can still cause hurt to the innocent victim.
After reading some commentaries and studying, I understand now that "curse" means something different. Here it means the invoking (or asking) of evil upon another, with no justification for it. Let's look at a couple of Bible references, and we can understand.
In I Samuel 17, we can read the familiar story of David and Goliath. If you have time, I hope you will re-read it, so that we can fully explore this. You'll see in verse 43 that Goliath cursed David by the Philistine gods. Nevertheless, in the power of God, David was triumphant over Goliath --- the curses were as ineffective as a tiny bird, fluttering about and never coming to light on David. The curse did not "come to rest" on him.
In the book of Numbers, Balak, king of Moab, hired a prophet of God, Balaam, for the purpose of cursing the children of Israel. Moab figured that way he could be victorious over them in the battle. Balaam warned him that he could not curse God's people, and he was right -- blessings came out of his mouth instead. Not once, but three times! (You can check it out in Numbers 22-24.) Because there was no justification for it, the curse did not "come to rest."
Another example is in II Samuel chapter 21: Shimei, who apparently was a very spiteful guy, pelted David with dirt and rocks, cursing him. He accused him of several things which David had actually not done (we know this by reading the chapters previous) and King David decided to restrain his soldiers, ignore the cursing, and arrive at his destination unscathed. Again, the curse did not come to rest.
In sharp contrast is the situation where Elisha cursed the "youths" (which actually must have been a mob, by most commentaries, as 42 were mauled by the bear) who were mocking and insulting him. Since Elisha was the prophet of God, it was as if they were mocking and insulting Him, and Elisha asked God to deal with them as He would. This was a curse with justification, and it definitely came to rest.
Again, in the ninth chapter of Judges, Jotham is the main character who curses both Abimelech, and the men of Shechem, who conspire, murder, and more, to install Abimelech as king. Jotham's curse of death by fire comes true later for the men of Shechem, and Abimelech dies an ignominious death, being felled by a millstone.
So, an undeserved curse will be harmless. To be cursed or insulted by mere men, for doing what is right, or what is good, will affect us only as much as a tiny bird flitting about. When we reprove evil, proclaim an unpopular truth, or pursue a righteous course which runs against popular opinion, we may be cursed. But what of it? The prophets of old were insulted, Christ was cursed and spat upon, and the disciples were mocked and cursed, as well.
Perhaps this is what Jesus referred to, when He said:
11 “Blessed are you when people insult you, persecute you and falsely say all kinds of evil against you because of me. 12 Rejoice and be glad, because great is your reward in heaven, for in the same way they persecuted the prophets who were before you. (Matthew 5:11-12)This has been a lengthy study, but I hope it will be a blessing for someone who needed to hear it, and be encouraged to "keep on keeping on."