Answer: This expression does not mean that Jesus always acts in the same way or is always doing the same work. Nor does it mean that He is always of the same nature, for He was first a spirit being, the Archangel. “In a beginning [so the Greek] was the Logos, and the Logos was with the God, and the Logos was a god [a mighty one]” (John 1: 1, see Diaglott). He was “the firstborn of every creature” (Colossians 1: 15), “the beginning of the creation of God” (Revelation 3: 14). In due time He was made flesh (John 1: 14) (Galatians 4: 4), that is, a human being. Then He died and was raised to the Divine nature and given a name above every name (Philippians 2: 6-10) (Hebrews 1: 3, 4). But He has been and is the same person in all three natures.

Therefore the “yesterday” of our text does not refer to past eternity, but to the Jewish Age, which is spoken of as a day (Isaiah 65: 2) (Romans 10: 21), while eternity is never called a day. A yesterday is a day before the present day. A day has a beginning, so has a yesterday, so the yesterday here cannot mean duration without a beginning, that is, eternity. The days of this passage are evidently ages, as is proven by the Greek expression here for “forever” which is literally rendered “for the ages.” Therefore, the word “today” in this verse apparently refers to the Gospel Age, also called a day (Acts 13: 33) (Romans 8: 36) (2 Corinthians 6: 2) (Hebrews 3: 13, 15). And this is not followed by the word tomorrow, for that would imply only one Age (the Millennial Age) for Jesus’ future existence. He will live forever – “for the ages,” a term expressive of eternity.

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