Berean Study Bible
I say this as a concession, not as a command.

King James Bible
But I speak this by permission, and not of commandment.

American Standard Version
But this I say by way of concession, not of commandment.

Darby Bible Translation
But this I say, as consenting [to], not as commanding [it].

Douay-Rheims Bible
But I speak this by indulgence, not by commandment.

English Revised Version
But this I say by way of permission, not of commandment.

Young's Literal Translation
and this I say by way of concurrence -- not of command,