Revelation 1:7
"and every eye shall see him"
https://biblehub.com/revelation/1-7.htm

1 Thessalonians 5:1-3 BSB
The Day of the Lord
1Now about the times and seasons, brothers, we do not need to write to you. 2For you are fully aware that the Day of the Lord will come like a thief in the night. 3While people are saying, “Peace and security,” destruction will come upon them suddenly, like labor pains on a pregnant woman, and they will not escape.…

Nederlandse Leeuw - Own work

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2 Corinthians 11:13-15
For such men are false apostles, deceitful workers, masquerading as apostles of Christ. / And no wonder, for Satan himself masquerades as an angel of light. / It is not surprising, then, if his servants masquerade as servants of righteousness. Their end will correspond to their actions.

"I Whistle a Happy Tune" is a famous song from the 1951 Rodgers and Hammerstein musical, The King and I.