“Behold, the hire of the labourers who have reaped down your fields, which is of you kept back by fraud, crieth: and the cries of them which have reaped are entered into the ears of the Lord of sabaoth” (James 5:4).
The King James Bible twice uses the title “the Lord of Sabaoth.” One instance is today’s Scripture. The other is Romans 9:29: “And as Esaias said before, Except the Lord of Sabaoth had left us a seed, we had been as Sodoma, and been made like unto Gomorrha.” Interestingly enough, if we search the Scriptures to find the words of “Esaias” (Greek form of “Isaiah”), we will learn what “the Lord of Sabaoth” means.
When the Apostle Paul penned Romans 9:29, the Holy Spirit led him to quote Isaiah 1:9: “Except the LORD of hosts had left unto us a very small remnant, we should have been as Sodom, and we should have been like unto Gomorrah.” Notice the accuracy of this divinely-inspired translation! Has anything been “lost in translation” as modern Bible textual critics often claim? No.
The Holy Spirit through Paul took the Hebrew words of the Book of Isaiah and translated them into Koine Greek to form part of the Book of Romans. We find the meaning of “the Lord of sabaoth” by simply reading Isaiah’s original wording: “the LORD of hosts.” Actually, sabaoth is the English transliteration of the Greek word (sabaoth) derived from the Hebrew word tsaba. Tsaba, or “hosts,” is the same word the Prophet Isaiah used.
In summary, the title “the Lord of Sabaoth” means “the Lord of Hosts.” Now, what does that mean? It signifies God’s military might—that is, His strength to fight and win battles. The LORD is commander-in-chief of the angelic soldiers and the human armies of Israel (“the LORD of hosts” is defined in 1 Samuel 17:45 as “the God of the armies of Israel”). Romans 9:25-29 and James 5:4 look forward to the day when the Lord Jesus returns to Earth in wrath—His Second Coming—to conquer Satan and destroy the wicked, Jew and Gentile (non-Jew) alike. source