1 Corinthians 4:21

What do ye wish? Shall I come to you with a rod, or in love and a spirit of gentleness?

2 Corinthians 10:6

and holding ourselves in readiness to avenge every disobedience, when your obedience is made complete.

2 Corinthians 13:2

I have said beforehand, and I do say beforehand, as if present at the second time, and, being now absent, I write to those who heretofore have sinned, and to all the rest; that, if I come again, I will not spare;

Treasury of Scripture Knowledge

Summary

A whip for the horse, a bridle for the ass, and a rod for the fool's back.

According to our notions, we should rather say, a bridle for the horse, and a whip for the ass; but it should be considered, that the eastern asses are not only much more beautiful, but better goers that ours; and being active and well broken, they need only a bridle to guide them; whereas their horses being scarce, and often caught wild, and badly broken, are much less manageable, and need the correction of the whip

Bible References

According to our notions, we should rather say, a bridle for the horse, and a whip for the ass; but it should be considered, that the eastern asses are not only much more beautiful, but better goers that ours; and being active and well broken, they need only a bridle to guide them; whereas their horses being scarce, and often caught wild, and badly broken, are much less manageable, and need the correction of the whip

1 Corinthians 4:21
What do ye wish? Shall I come to you with a rod, or in love and a spirit of gentleness?
2 Corinthians 10:6
and holding ourselves in readiness to avenge every disobedience, when your obedience is made complete.
2 Corinthians 13:2
I have said beforehand, and I do say beforehand, as if present at the second time, and, being now absent, I write to those who heretofore have sinned, and to all the rest; that, if I come again, I will not spare;