beginning from the baptism of John until the day when he was taken up from us—one of these men must become with us a witness to his resurrection.”
The sin of Judas was not only his shame and ruin, but it made a vacancy in the college of the apostles. They were ordained twelve, with an eye to the twelve tribes of Israel, descended from the twelve patriarchs; they were the twelve stars that make up the church's crown (Rev 12:1), and for them twelve thrones were designated, Mat 19:28.
Commenting on Acts 1:15-26
Beginning from the baptism of John,.... Not from the time trial John first administered the ordinance of baptism; for Christ was not so soon made known, or had followers; but from the time of the administration of it by John, to Christ, when he was made known to Israel; and quickly upon this, he called his disciples, and entered on his public ministry: now Peter...
Verse 22. (*) "ordained" or, "Appointed"