Jesus also noted, in addition to the adulteress, when he healed the cripple at the Bethesda pool, to sin no more, or something worse might happen.

In both cases Jesus forgave, but also gave a warning as to future sins, nor did he note the penalty was void.

In some cases capital punishment may be a blessing, in that it allows a sinner to repent, which is not the prerogative of those who die suddenly, & unexpectedly.