As we read Ephesians 4:32 we see an issue that is too big to fail. The reason to be loving and kind in our communication is directly related to how God treats us through Jesus. Love and kindness is not about brushing off issues, but a pathway in how we engage situations.
The fact that God forgives all our sin is massive. All means all. When we act out against someone harshly, vs the way the verse describes, we are saying that there is an issue that God can forgive than I cannot. For sure people can do massively hurtful things. As a world changer, forgiveness is a remarkable tool for not only healing, but building the offender up. It changes things.
The verse also teaches us that God did not crush us for our offensives, but that God worked in such a way to bring healing and restoration. Jesus took on the full crushing weight of our offenses when he died on the cross for us. Living distinctly Christian lives means living with that kind of love. Again, this does not mean we brush offenses off, but it does instruct in how we engage in those offenses.
The golden rule is loved unless we have to act on it. Being kind and tenderhearted is work. Some are gifted in such a way that it comes easy, but for a majority it is challenging work. Especially the forgiveness aspect. But the world changing power of living it out is Earth shattering.