"And a certain ruler questioned him, saying, `Good teacher, what having done -- shall I inherit life age-during? And Jesus said to him, `Why me dost thou call good? no one [is] good, except One -- God;"
Luke 18:18-19 (Young's literal translation)
Let's face the truth. No one is good. You cannot call yourself good, because even Jesus did not. It's not about the authority game here, but the truth. Jesus had not sinned even once in his 33 years. How much had we, even after we are being saved? Even after we made efforts to abide the word of God? Let's get this clear man. When you make an effort to abide by God's word, he is very glad and proud of you. You can see that big, wide grin on his face, and saying "good job, daughter/son, you have made an effort to follow me!"
But that does'nt make you good. Doing a good deed does not make a person good. Of course it's good to do a good deed. But what about our sins? That prevents us from being called good. And compare ourselves to Christ. He had not even sinned once in his 33 years, and yet he did not call himself good. Therefore, no one is good. No christian is good.
Don't call yourself a good christian. Call yourself a strong faithful one, a strong one. Call your friends a strong believer, a faithful christian. Don't call him a good christian. I am not trying to say that you should not praise your friends too much. In fact, the bible is full of verses telling us to love, encourage, praise! God is not a legalistic God. He is not the type of God who says "if you praise your friend 10 times, you must praise me 20 times". That's not God's character. He just wants you to love him with all your heart, soul and strength. God sees from your heart. He totally deserves to be in the first place in our lives. It's fine if you don't put him, yea, and your life will screw up. It's totally wrong to regard God as a sideliner. He is not the sideline referee, he is not the player, he is not the commentator, he is not the spectator, he is not the advisor. He MUST BE your coach. He MUST BE the first place in your lives. Regarding him as a sideliner is a totally short-termed, short-sighted, short-goaled, and totally wrong perspective for your life. It's disrepsect and self-centeredness.
So, don't say "good christian", say "faithful christian, strong christian". It's more specific, and, more accurate. Much more. Don't call a person good, but by all means, commend that the things he DID(not the person) as "good". Don't even call yourself good. Only one person is good - God. Only God is good.