But Peter said, Ananias, why hath Satan filled thine heart to lie to the Holy Ghost, and to keep back part of the price of the land? Why hath Satan filled thine heart - The verb πληροειν, which we translate to fill, Kypke has showed by many examples to signify, to instigate, excite, impel, etc., and it was a common belief, as well among the heathens as among the Jews and Christians, that, when a man did evil, he was excited to it by the influence and malice of an evil spirit. It is strange that, by the general consent of mankind, sin against God has been ever considered so perfectly unnatural, and so evil in itself, that no man would commit it unless impelled to it by the agency of the devil. The words of St. Peter here prove that such an agency is not fictitious: if there had been no devil, as some wish and perhaps feel it their interest to believe, or if this devil had no influence on the souls of men, Peter, under the agency of the Holy Spirit, would not have expressed himself in this way; for, if the thing were not so, it would have been the most direct means to lead the disciples to form false opinions, or to confirm them in old and absurd prejudices.
To lie to the Holy Ghost - Ψευσασθαι το Πνευμα το Ἁγιον, To deceive the Holy Spirit. Every lie is told with the intention to deceive; and they wished to deceive the apostles, and, in effect, that Holy Spirit under whose influence they professed to act. Lying against the Holy Ghost is in the next verse said to be lying against God; therefore the Holy Ghost is God.
To keep back part of the price - Νοσφισασθαι απο της τιμης. The verb νοσφιζειν, νοσφιζεσθαι, is used by the Greek writers to signify purloining part of the public money, peculation. The word is used here with great propriety, as the money for which the estate was sold was public property; as it was for this purpose alone that the sale was made.