'Power' in the Bible

for our good news [regarding salvation] came to you not only in word, but also in [its inherent] power and in the Holy Spirit and with great conviction [on our part]. You know what kind of men we proved to be among you for your benefit.

For the word of the Lord has resounded from you and has echoed [like thunder], not only in Macedonia and Achaia, but in every place [the news of] your [great] faith in God has spread, so that we never need to say anything about it.

And we also thank God continually for this, that when you received the word of God [concerning salvation] which you heard from us, you welcomed it not as the word of [mere] men, but as it truly is, the word of God, which is effectually at work in you who believe [exercising its inherent, supernatural power in those of faith].

But you, believers, [all you who believe in Christ as Savior and acknowledge Him as God’s Son] are not in spiritual darkness [nor held by its power], that the day [of judgment] would overtake you [by surprise] like a thief;