In short, the only reason given in Scripture that the Son of God willed to take our flesh, and accepted this commandment from the Father, is that he would be a sacrifice to appease the Father on our behalf. "Thus it is written, that the Christ should suffer . . . and that repentance . . . should be preached in his name." [Luke 24:46-47.] "For this reason the Father loves me, because I lay down my life for my sheep. … This commandment he gave me." [John 10:17, 15, 18 p.] "As Moses lifted up the serpent in the wilderness, so must the Son of Man be lifted up." [John 3:14.] Another passage: " 'Father, save me from this hour.' … But for this purpose I have come to this hour. Father, glorify thy Son" [John 12:27-28, conflated with v. 23]. Here he clearly indicates why he assumed flesh: that he might become a sacrifice and expiation to abolish our sins. – Calvin’s Institutes 2.12.4
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