I think it is scriptural, Biblical and therefore proper. Even God practiced it.
For those who ask for evidence:
Exodus 31:14 "Ye shall keep the sabbath therefore; for it is holy unto you: everyone that profaneth it shall surely be put to death; for whosoever doeth any work therein, that soul shall be cut off from among his people.” Cut off is the Hebrew karath: it means cut down, destroy, eliminate. These people were cut off - in death, yes, but cut off from everybody in Israel including their family. Miriam was struck with leprosy and cut off for seven days, Aaron pleaded with God for mercy and Moses interceded. Why would anybody think God would punish Miriam for the serious act of complaining against Moses but just ignore a worshiper practicing fornication?
Leviticus 18:29: “Any person who does any of these detestable practices is to be cut off from his people." Mathew Henry’s Commentary on verse 29 reads: “the souls that commit them shall be cut off -- This strong denunciatory language is applied to all the crimes specified in the chapter without distinction: to incest as truly as to bestiality, and to the eleven cases of affinity [ Lev 18:7-16 ], as fully as to the six of consanguinity [ Lev 18:17-20 ]. Death is the punishment sternly denounced against all of them. No language could be more explicit or universal; none could more strongly indicate intense loathing and abhorrence.”
Some (but not all) rabbinic scholars believe that the cutting off was only expulsion from the congregation of Israel. Opinions differ. They would still be cut off - excommunicated - disfellowshipped from the congregation.
1 Corinthians 5:11: ” But actually, I wrote you not to associate with anyone who claims to be a brother or sister and is sexually immoral or greedy, an idolater or verbally abusive, a drunkard or a swindler. Do not even eat with such a person.” Jamieson Fausset Brown Commentary on this verse: “Put away from among yourselves that wicked -- Sentence of excommunication in language taken from Deu 24:7.
Matthew Henry Commentary on this verse: “Though the church has nothing to do with those without, it must endeavour to keep clear of the guilt and reproach of those within. How he applies the argument to the case before him: "Therefore put away from among yourselves that wicked person, v. 13. Cast him out of your fellowship, and avoid his conversation.'
Finally, God kicked out Adam and Eve from the paradise Garden of Eden. God kicked out disobedient angels from heaven. It is ridiculous for a Christian to suggest that another Christian can practice anything he wants and still worship God along with God's faithful servants. The church must be clean and remain clean. If he doesn't want to stop his sin, out he goes until he does want to be clean.