Deuteronomy 10:16

“Circumcise therefore the foreskin of your heart, etc.] Content not yourselves with, nor put your confidence in outward circumcision of the flesh, but be concerned for the circumcision of the heart; for removing from that whatever is disagreeable to the Lord, even all carnality, sensuality, hypocrisy, and superfluity of naughtiness, and for having that put there which is well pleasing in his sight; and which though it is the work of God, and he only can do it and has promised it, yet such an exhortation is made to bring men to a sense of their need of it, and of the importance of it, and to show how agreeable it is to the Lord, and so to stir them up to seek unto him for it; (see…”

“Circumcise therefore the foreskin of your heart--Here he teaches them the true and spiritual meaning of that rite, as was afterwards more strongly urged by Paul (Rom 2:25, Rom 2:29), and should be applied by us to our baptism, which is "not the putting away of the filth of the flesh, but the answer of a good conscience toward God" [Pe1 3:21]. Next: Deuteronomy Chapter 11”

“On “circumcision” see Genesis 17:10. This verse points to the spiritual import of circumcision. Man is by nature “very far gone from original righteousness,” and in a state of enmity to God; by circumcision, as the sacrament of admission to the privileges of the chosen people, this opposition must be taken away ere man could enter into covenant with God. It was through the flesh that man first sinned; as it is also in the flesh, its functions, lusts, etc., that man’s rebellion against God chiefly manifests itself still. It was fitting therefore that the symbol which should denote the removal of this estrangement from God should be worked in the body. Moses then fitly follows up the command…”

“Circumcise - Rest not in your bodily circumcision, but seriously set upon that substantial work which is signified thereby: cleanse your hearts from all filthiness and superfluity of naughtiness, fitly compared to the foreskin, which if not cut off, made persons profane, unclean and odious in the sight of God. Deuteronomy 10:17”

“10:16 change your hearts (literally circumcise the foreskin of your hearts): This figure of speech encompasses both inward and outward conformity to the covenant (Gen 17:9-14; Rom 2:28-29).”

“Circumcise: Deu 30:6; Lev 26:41; Jer 4:4, Jer 4:14; Rom 2:28, Rom 2:29; Col 2:11 stiffnecked: Deu 9:6, Deu 9:13, Deu 31:27; Jam 4:6, Jam 4:7 Deuteronomy 10:17”

“Above all, therefore, they were to circumcise the foreskin of their hearts, i.e., to lay aside all insensibility of heart to impressions from the love of God (cf. Lev 26:41; and on the spiritual signification of circumcision, see Gen 17:15-21), and not stiffen their necks any more, i.e., not persist in their obstinacy, or obstinate resistance to God (cf. Deu 9:6, Deu 9:13). Without circumcision of heart, true fear of God and true love of God are both impossible. As a reason for this admonition, Moses adduces in Deu 10:17. the nature and acts of God. Jehovah as the absolute God and Lord is mighty and terrible towards all, without respect of person, and at the same time a just Judge and loving…”