Jesus commanded us to go into the world and share the Gospel, which also means sharing the Gospel right at home.
If we Christians would learn how to appeal to not only the lost world, but other Christians with an attitude of love and gentleness how much better off would we be? How many more souls could we influence if we showed love rather than judgment and criticisms? By no means am I saying we should be tolerant of blatant sin, God forbid. But we must be careful about holding others to standards that perhaps God has not led them to. And oh how often have we been in error over convictions in the past? It's called learning, being sanctified! It is the Holy Spirit that convicts our hearts, and some times it is our own self-righteousness!
Christians should strive to walk in a spirit of love with each other, yet so often that seems to be the crowd with the sharpest tongue!
In Scripture we are told about the Believing wife that lived with her unbelieving husband. Basically she is told that she can win Him over to God without saying a word, because we all know that it is actions that truly speak.
We can lead people to Christ more by example (humble service, love, kindness, etc...) than we can with words. And we sure can't influence them with a critical spirit.
By this shall all men know that ye are my disciples,
if ye have love one to another.
With all lowliness and meekness, with longsuffering,
forbearing one another in love;