The argument that Paul and other early Christians would not have known about loving, committed, long-term homosexual relationships, unions, or even marriages is false. A myth has developed in contemporary ‘scholarship’ about what antiquity understood on these matters, perpetuated by scholars who refuse to do the heavy lifting work of actual research in the primary sources rather than just quote one another. It is as though the argument has been hermetically sealed by those pushing the revisionist agenda of same-sex unions: actual research would be highly inconvenient were it to reveal the myth.
The mistaken scholarship seems to have begun in the 1980s with Robin Scroggs, who argued that
… pederasty was the only model [for homosexuality] in existence in the world of [Paul’s] time.” And “at the risk of seeming endlessly repetitive, I close with the observation that Paul thinks of pederasty, and perhaps the more degraded forms of it, when he is attacking homosexuality.