'Day and Night' in the Bible

And each of the four living beings had six wings [and] were covered with eyes all around them and [even] within them. And day and night they never stop saying, [Note: Some translations have "singing" here and at other places below], "Holy, holy, holy [is] the Lord God Almighty, who was [in the past] and who is [in the present] and who will come [in the future]."

So, [now] they are in front of God's throne and they are serving Him day and night in His Temple. And He who sits on His throne will spread His tent over them [i.e., He will protect them].

And I heard a loud voice in heaven saying, "The salvation and the power and the kingdom of our God, and the authority of His Christ, have [all] now come. For the one who accuses our brothers in front of God day and night has been thrown out [of heaven].

And the devil who [had] deceived them was thrown into the lake of fire, [burning] with sulphur, where the beast and the false prophet also are. [See 19:20]. And [there] these [enemies of God] will be tortured day and night forever and ever.