Resignation Becomes Complete Once the Employer Accepts
Resignation is one of the rights of the employee set forth under Article 300 of the Labor Code, as amended. It can be voluntary or involuntary. The latter being based on just cause enumerated in the article like serious insult, abuse, etc.
In the case of Intertrod Maritime, Inc. vs. National Labor Relations Commission (G.R. No. 81087, June 19, 1991), the Supreme Court held that resignation is the voluntary act of an employee who “finds himself in a situation where he believes that personal reasons cannot be sacrificed in favor of the exigency of the service, then he has no other choice but to disassociate himself from his employment.”
The employer has no control over resignations and so, the notification requirement was devised in order to ensure that no disruption of work would be involved by reason of the resignation.
This practice has been recognized because “every business enterprise endeavors to increase its profits by adopting a device or means designed towards that goal.”
Resignations, once accepted and being the sole act of the employee, may not be withdrawn without the consent of the employer.
In the a case where the Master had already accepted the resignation and, although the employee was being required to serve the thirty (30) days notice provided in the contract, his resignation was already
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approved.
The employee cannot claim that his resignation ceased to be effective because he was not immediately discharged from his post, for he could no longer unilaterally withdraw such resignation. When he later signified his intention of continuing his work, it was already up to the employer to accept his withdrawal of his resignation.
The mere fact that the employer did not accept such withdrawal did not constitute illegal dismissal for acceptance of the withdrawal of the resignation was their the employer’s sole prerogative.
Once an employee resigns and his resignation is accepted, he no longer has any right to the job. If the employee later changes his mind, he must ask for approval of the withdrawal of his resignation from his employer, as if he were re-applying for the job. It will then be up to the employer to determine whether 
or not his service would be continued.
If the employer accepts said withdrawal, the employee retains his job. If the employer does not, as in this case, the employee cannot claim illegal dismissal for the employer has the right to determine who his employees will be.
To say that an employee who has resigned is illegally dismissed, is to encroach upon the right of employers to hire persons who will be of service to them.
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