Jesus is described as “the son of man” over 80 times in Matthew, Mark, Luke, and John. Most of the time, with only a couple of exceptions, Jesus is the one who used this phrase. Moreover, he was using this phrase to describe himself (e.g. Mark 2:10; John 3:14; Matthew 16:13).
What does this phrase mean? (1) It refers to his humanity. (a) Psalm 8:4 reads, “What is man that You are mindful of him, and the son of man that you visit him?” Notice the parallelism. “Man” is parallel with “the son of man.” This parallel is found in many Old Testament passages (e.g. Number 23:19; Job 16:21; 25:6; 35:8; Psalm 80:17; 144:3-4; Isaiah 51:12; 56:2; Jeremiah 49:18, 33; 50:40; 51:43). (b) Others are referred to as “son of man.” Ezekiel is referred to by this phrase over 90 times in the book of Ezekiel. Daniel is referred to this way once in the book of Daniel. This is done to emphasize their humanity, and relationship to God and man (cf. Ezekiel 3:17-19). (c) The words “son of…” sometimes refers to being “of the order of” (Zondervan’s Pictorial Dictionary, p. 805) or “membership in a class or guild” (I.S.B.E. Vol. 4, p. 2826). It is used of: one who is a perfumer, Nehemiah 3:8, see NKJV fn; one of the goldsmiths, Nehemiah 3:31; those who are singers, Nehemiah 12:28; a prophet or one associated with a prophet, Amos 7:14.
Jesus was fully human. He grew tired and needed sleep (John 4:6; Mark 4:38). He experienced hunger and thirst (Matthew 4:2; John 4:6-7; 19:28). He was tempted (Mark 1:13; Hebrews 4:15). He even tasted death (Hebrews 2:9).
(2) More may be intended. He was the promised human. He was the promised seed (Genesis 3:15; 12:3; 22:18). This son of man was written of in scripture aforetime. Jesus said, “The son of man indeed goes just as it is written of Him…” (Matthew 26:24). It was foretold that a man would come, who would suffer for us (Isaiah 53). Moreover, one like the son of man would go to the Ancient off Days and would be given an everlasting kingdom (Daniel 7:13-14 cf. Acts 1:9; 2:33, 36). Remember that Jesus came in the likeness of man (Romans 8:3; Philippians 2:7; Hebrews 2:17).
Let us summarize. His humanity is in view. “ ‘Son of man’ seems to mean essentially, man, a distinct member of the order of humanity” says Zondervan’s Pictorial Dictionary (p. 805). However, more may be intended. He is the one prophesied of in scripture. He is the promised one.