The two acts, side by side
An acknowledgment answers one question: did this person sign, and did they do it willingly? The signature can predate the appointment by weeks. This is the act used for deeds, mortgages, powers of attorney, and most contracts, because what matters is authenticity of the signature, not truth of the terms.
A jurat answers a different question: did this person swear the contents were true, in front of me, at the moment they signed? That is why affidavits, verified petitions, annual court accountings, and sworn financial statements use jurats. The perjury exposure is the whole point, and it is why the signature cannot be pre-made.
