Matthew Poole and continuators on Acts 15:9

9 And put no difference between us and them, purifying their hearts by faith.

God had now broken down the middle-wall of partition betwixt Iew and Gentile, and distributed his graces to these also, Ephes. 2.14. which was signified by the rending of the vail from the top to the bottom, Matthew 27.51. whereby such as were formerly without, might see, and injoy the benefit of those great things which had been hidden under those shadows and types.

From Idolatry, and other impieties in which they had lived; which is the inward circumcision of the heart; and whosoever is thus cleansed, ought not to be reputed amongst the unclean.

Faith is the instrument, God is the efficient cause of our Justification and Renovation.

Marginal references: Chap. 10.43. 1 Cor. 1.2. 1 Pet. 1.22.