John Lightfoot on Luke 3:2

[Annas and Caiaphas being high priests.] They do constitute two high priests at one time. True indeed: but they promoted a sagan, together with a high priest.

The 'sagan,' as to his degree, was the same to the high priest, as he that was next or second to the king.

They substituted, indeed, on the vespers of the day of expiation, another priest to the high priest, that should be in readiness to perform the office for the day, if any uncleanness should by chance have befallen the high priest.

"It is storied of Ben Elam of Zipporim, that when a gonorrhea had seized the high priest on the day of expiation, he went in and performed the office for that day. And another story of Simeon Ben Kamith, that as he was walking with the king on the vespers of the day of expiation, his garments were touched with another's spittle, so that Judah his brother went in and ministered. On that day the mother of them saw her two sons high priests."

It is not without reason controverted, whether the sagan were the same with this deputed priest: the Jews themselves dispute it. I would be on the negative part: for the sagan was not so much the vice high priest, as (if I may so speak) one set over the priests. The same with the ruler of the temple; of whom we have such frequent mention among the doctors: upon him chiefly did the care and charge of the service of the temple lie.

"The ruler of the temple saith to them, Go out and see if it be time to slay the sacrifice." "The ruler saith, Come and cast your lots who shall slay the sacrifice, who shall sprinkle the blood," &c. The Gloss is, the ruler is the 'sagan.'

He is commonly called the 'sagan' of the priests: which argues his supremacy among the priests, rather than his vicegerency under the high priest.

"When the high priest stands in the circle of those that are to comfort the mourners, the sagan and he that is anointed for the battle, stand on his right hand, and the head of the father's house, those that mourn, and all the people stand on his left hand."

Mark here the order of the sagan; he is below the high priest, but above the heads of all the courses.

2 Kings 23:4, the priests of the second order: Targum, the 'sagan' of the priests. And chapter 25:18, Zephaniah the second priest: Targum, Zephaniah 'the sagan' of the priests.

Caiaphas therefore was the high priest, and Annas the sagan or ruler of the temple; who, for his independent dignity, is called high priest as well as Caiaphas; and seems therefore to be named first, because he was the other's father-in-law.

There was a dissension between Hanan and the sons of the chief priests, &c. It was in a judicial cause, about a wife requiring her dower, &c. Where the scruple is, who should these chief priests be? whether the fathers and heads of the courses, or the high priest only and the sagan. It was a council of priests: which we have already spoken to at Matthew 26:3. Now the question is, whether by the "sons of the chief priests," be meant the sons of the fathers of courses, or the fathers of courses themselves, or the sons of the high priest and the sagan; where the high priest in that court was like the prince in the Sanhedrim, and the sagan the father of the Sanhedrim.

"Moses was made a sagan to Aaron. He put on his garments, and took them off [viz. on the day of his consecration]. And as he was his sagan in life, so he was in death too."