Jesus allowed sinners to be around him too. While I couldn’t be a member of a church that would have an unrepentant abortionist as a member, there are reasons why a minister may have allowed him to be there - perhaps to slowly influence him through the Holy Spirit to repent or perhaps to minister to his wife to confront him about his work. We don’t know and can’t know.
Yes, there are many liberals churches now that embrace all sorts of sin and apostasy but I will not condemn Tiller’s church without knowing what was their intent on allowing him to be there and to serve as an usher. Maybe he kept a low profile and few knew what his occupation was or perhaps they thought they could minister to him and, over time, convince him to change.
God used Saul of Tarsus for His purposes even though Saul intended to persecute and kill Christians.
IMO, a church should be a place of peace. I don’t like seeing it disrupted by violence, even violence some would feel is justified.
Jesus also said go and sin no more he did not say sin all you want and I will forgive you....this person sinned every day by murdering innocent little children.. I do not condone what happened in that so called church but I also do not condone the murder of little babies by sucking their brains out and crushing their heads to get the baby out of the mother..Only God can and will punish this evil person..