Wisdom and discernment are not enemies of forgiveness
Let's think about the following hypothetical scenario:
Bubba was the treasurer for a megachurch. Over the course of ten years, he managed to embezzle one million dollars from the church before he was caught. He spent about six months in prison and is now in probation. He has moved back to his hometown and has applied to be the treasurer at the church where his parents are members. The church, seeing his criminal history, said "no." They hired someone else.
Bubba's parents are angry, because his resume clearly establishes him as the best candidate for the job. His education, skills and experience are all far and away above the other applicants, who have no history of theft. Why can't this church accept that this man has repented and has been forgiven by Jesus?
Of course, they do accept that Bubba has repented and is forgiven, but they still will not hire him. Why? Well, primarily, because they are not stupid. They know money is a temptation for Bubba, and they want to protect him from sin by not providing him with the temptation to steal. They also want to protect their own church's finances.
Yes, Bubba has repented. Yes, Bubba is forgiven. Yes, the church absolutely should welcome him to fellowship, communion, and their small group. But you would have to be a complete idiot to not recognize that greed is probably still a temptation. It is not loving to put Bubba in a position where he could be tempted to steal. It is pure hatred.
This is where a lot of Christians get confused. While we are forgiven by Jesus and washed of our sins, we still are at war with our sin nature and will be until the day we die. Everyone has different temptations. Bubba's besetting sin is greed, while others deal with lust, fornication, pornography, anger, bitterness, lying, or other things.
If someone has a particular besetting sin, it is wise to help him in his sanctification by not making that sin accessible to him. This is especially important when that sin harms others, because the church has a responsibility to protect the innocent as well as aid sinners in our war with our sin nature. Recognizing the reality that we all face does not in any way mean that someone with a particular besetting sin is not justified and will not spend eternity with Jesus.
Note: The characters in this story are entirely fictional. This is purely to make a point.