Short answer. Yes. When your principal is present and hands you a power of attorney that you accept without any objection, the Civil Code treats your silence as implied acceptance. You are bound as agent from that moment, even without a spoken or written declaration.
What the law says
the acceptance of the agency may also be implied if the principal delivers his power of attorney to the agent and the latter receives it without any objection
Civil Code, Article 1871 — Implied Acceptance (Present Parties). Read the full provision →
What Article 1871 provides
Article 1871 of the Civil Code states that between persons who are present, acceptance of the agency may be implied rather than expressed. The triggering act is simple: the principal physically delivers the power of attorney to the agent, and the agent receives it without raising any objection. No spoken words or signed acknowledgment are required. The law treats this exchange as a complete and binding acceptance of the agency relationship.
Why silence can bind you here
In most situations, silence does not equal consent. Agency is a recognized exception when the parties stand face to face and the agent takes physical possession of the document of authority. The reasoning is practical: if you genuinely did not want the appointment, the natural response is to hand the document back or say so. Receiving the power of attorney without objection sends an unmistakable signal that the law elevates to formal acceptance. You cannot later deny the relationship on the ground that you never said yes out loud.
What becoming an agent obliges you to do
Once acceptance is implied, the full set of agent's duties attaches. You must act within the authority granted, exercise the care of a good father of a family, keep the principal informed, and account for everything received. If you exceed the scope of the power of attorney or act in your own interest at the principal's expense, you bear personal liability. Accepting the document without objection and then acting under it makes it especially difficult to later contest that the relationship ever formed.
When this implied-acceptance rule does not apply
Article 1871 operates only when both principal and agent are present at the moment of delivery. If the power of attorney is sent by mail, courier, or any other means where you are physically absent, silent receipt does not carry the same legal consequence — a different set of rules applies to absent parties. Likewise, if you accept the document but immediately return it or clearly refuse the appointment on the spot, no implied acceptance arises — the timely objection breaks the chain the article describes.