You are, right now, whatever is in your mind. As a man thinks in his heart, so is he. The mental attitude of long-suffering recognizes the spiritual progress, or lack of progress, of other people. Every person in a congregation is either growing in Christ or is in a state of backsliding, reversion. Long-suffering is patience towards other people.
Every community has people who are hateful, implacable, antagonistic, bitter, vengeful.
These people malign, gossip, judge, criticize, complain, ostracize. A long-suffering Christian does not hate, does not seek revenge, does not malign or gossip, is not jealous or envious, does not counterattack. Long-suffering does not mean that you pat your foot and wait for your chance. You can be stable and take a stand because of Bible truth in your soul. You can refrain from an improper response because you know the correct response.