No, when a second param is passed to the log_enable function that tells the SQL session to set the transaction logging mode to that value on completion of executing the command. Thus
log_enable(3,1) will set the transaction logging mode to 3 for the execution of the next command and then automatically set it back to the default of 1 on completion.
If you want the session to remain in a given transaction logging mode then you would just pass one param ie
log_enable(3) for example and then all command for a given SQL session would run in that transaction logging mode until either it is changed again or the session ends and any new sessions would run in the default transaction logging mode of 1.