What is the biblical argument against having a concubine? It is generally accepted that "having a concubine" = "not socially accepted." However,


Solomon had 700 wives and 300 concubines.
Having concubines was mentioned in the Old Testament.
I cannot find any New Testament verse against having concubines.


Thus, the question:

What is the scriptural evidence against a man having a concubine?
Overseers and deacons are told to be a one woman man in the pastoral epistles, and Christians are told to model the behavior of these men. (1 Timothy 3:12)

Additionally, Ephesians 5 roots the institution of marriage in creation and demonstrates that its intent was always to point to the profound mystery revealed: Christ's marriage to the church. As a picture of a healthy monogamous marriage in pre-fallen creation, it demonstrates that the creation ideal of marriage applies to Christian marriages. 

As Jesus said that certificates of divorce were allowed due to hardness of heart (Matthew 19:8) but in the beginning it was not so, he demonstrates that for a time, these non-ideal marriages were permitted though they were never a good thing. As people indwelled by the Spirit, they were expected to be in line with the restoration of creation, and the modeling of the Christ/Church marriage. 

Finally, Calvin himself denounced Lamech and Laban as perverters of the original mandate for having one wife in his commentary on Genesis.