John Wesley on Hebrews 2:17

Wherefore it behoved him - It was highly fit and proper, yea, necessary, in order to his design of redeeming them. To be made in all things - That essentially pertain to human nature, and in all sufferings and temptations. Like his brethren - This is a recapitulation of all that goes before: the sum of all that follows is added immediately. That he might be a merciful and faithful High Priest - Merciful toward sinners; faithful toward God. A priest or high priest is one who has a right of approaching God, and of bringing others to him. Faithful is treated of, Heb 3:2, &c., with its use; merciful, Heb 4:14, &c., with the use also; High Priest, Heb 5:4, &c., Heb 7:1, &c. The use is added from Heb 10:19. In things pertaining to God, to expiate the sins of the people - Offering up their sacrifices and prayers to God; deriving God's grace, peace, and blessings upon them.