Alphaeus is mentioned in the New Testament as the father of two of the Twelve Apostles, namely:

There may have been two separate men named Alphaeus. Though both Matthew and James are described as being the "son of Alphaeus" there is no Biblical account of the two being called brothers, even in the same context where John and James or Peter and Andrew are described as being brothers.

Alphaeus is traditionally identified with Clopas, based on the identification from parallel Gospel accounts of Mary, the mother of James the third woman with Mary Magdalene and Salome wife of Zebedee beside the cross in Matthew with Mary, the wife of Clopas, the third woman in John's account. The Catholic Encyclopedia suggest that etymologically, the names "Clopas" and "Alphaeus" are different, but that they could still be the same person. Other sources propose that Alphaeus, Clophas and Cleophas are variant attempts to render the Aramaic "H" in Aramaic Hilfai into Greek as aspirated, or "K."

The apostle called Simon Zelotes, Simon the Zealot, in Luke 6:15 and Acts 1:13; and Simon Kananaios or Simon Cananeus ("Simon" signifying שמעון "hearkening; listening", Standard Hebrew Šimʿon, Tiberian Hebrew Šimʿôn), was one of the most obscure among the apostles of Jesus. Little is recorded of him aside from his name. A few pseudepigraphical writings were connected to him, and Jerome does not include him in De viris illustribus.

The name of Simon occurs in all of the synoptic gospels and Acts that give a list of apostles, without further details:

To distinguish him from Simon Peter, he is called Kananaios, or Kananites (Matthew 10:4; Mark 3:18), and in the list of apostles in Luke 6:15, repeated in Acts 1:13, Zelotes, the "Zealot". Both titles derive from the Hebrew word qana, meaning The Zealous, though Jerome and others mistook the word to signify the apostle was from the town of Cana, in which case his epithet would have been "Kanaios" or even from the region of Canaan. As such, the translation of the word as "the Cananite" or "the Canaanite" is traditional and without contemporary extra-canonic parallel.

Saint James, son of Alphaeus (Ἰάκωβος, Iakōbos in Greek) was one of the Twelve Apostles of Jesus Christ, appearing under this name in all three of the Synoptic Gospels' lists of the apostles. He is often identified with James the Less (Greek Iacobos ho mikros, Ἰακώβος ο μικρος Mark 15:40) and commonly known by that name in church tradition. He is also labelled "the minor", "the little", "the lesser", or "the younger", according to translation.

James, the son of Alphaeus, is rarely mentioned in the New Testament. He is distinguished from James the Lord's brother (Gal.1:19), an important leader in the New Testament church, and James, son of Zebedee, another one of the Twelve Apostles.

James, son of Alphaeus, appears only four times in the New Testament, each time in a list of the twelve apostles.

James, son of Alphaeus is often identified with James the Less, who is only mentioned three times in the Bible, each time in connection with his mother. Mark 15:40 refers to "Mary the mother of James the younger and of Joses", while Mark 16:1 and Matthew 27:56 refer to "Mary the mother of James". He is rarely identified with James, traditionally half-brother of Jesus^{[citation needed]}.