"Good faith is "an elusive idea, taking on different meanings and emphases as we move from one context to another."56 It is, in general, a state of mind consisting in honesty in belief or purpose, faithfulness to one's duty or obligation, observance of reasonable commercial standards of fair dealing in a given trade or business, absence of intent to defraud or seek unconscionable advantage,57 or a belief in one's legal title or right.58 Being malum in se, and depending on the proven circumstances, good faith and lack of criminal intent are indeed available defenses against a prosecution for Estafa.
However, all-encompassing this definition is, good faith still cannot be appreciated in favor of Arriola. As earlier expounded, Arriola, a real estate broker, presented to Del Rosario an Authorization and a fax transmission clearly conveying mere permission from Candelaria to receive payment from Del Rosario. Despite knowledge of such information, and even going so far as to disclose the same to Del Rosario, Arriola continued to wield his ultra vires power to sell Candelaria's lot. This smacks of overt thoughtlessness, gross negligence, and fraudulent intentions in his professional dealings, imperiling the welfare of both his principal and the latter's client and culminating in the actual damage to Del Rosario. To attribute good faith to Arriola under these facts is to uphold injustice."
G.R. No. 199975, February 24, 2020
LUIS T. ARRIOLA, PETITIONER, V. PEOPLE OF THE PHILIPPINES, RESPONDENT.
https://lawphil.net/judjuris/juri2020/feb2020/gr_199975_2020.html