God admonishes you [hereby] lest you ever revert to the like of this [sin], if you are [truly] believers;

God doth admonish you, that ye may never repeat such (conduct), if ye are (true) Believers.

Allah admonisheth you that ye repeat not the like thereof ever, if ye are (in truth) believers.

Allah admonishes you that you return not to the like of it ever again, if you are believers.

Allah warns you against returning to the likes of this [conduct], ever, if you should be believers.