“We do not have a High Priest who cannot sympathize with our weaknesses, but was in all points tempted as we are, yet without sin. Let us therefore come boldly to the throne of grace, that we may obtain mercy and find grace to help in time of need” (Heb. 4: 15, 16)
The gospel of God is “concerning His Son Jesus Christ our Lord, who was born of the seed of David according to the flesh” (Rom. 1:3). Read the history of David, and of the kings who descended from him, and who became the ancestors of Jesus, and you will see that on the human side the Lord was handicapped by His ancestry as badly as anybody can ever be. Many of them were licentious and cruel idolaters. Although Jesus was this compassed with infirmity, He “committed no sin, nor was guile found in His mouth.” 1 Pet. 2:22). This is to give courage to people in the lowest conditions of life. It is to show that the power of the gospel of the grace of God can triumph over heredity.
As with Christ, so with us; it is through much tribulation that we enter the kingdom. He who fears reproach, or who makes his lowly birth, or his inherited traits, and excuse for his shortcomings, will fail of the kingdom of heaven. Jesus Christ went to the lowest depths of humiliation in order that all who are in those depths might, if they would, ascend with Him to the utmost heights of exaltation.
“Therefore, since Christ suffered for us in the flesh, arm yourselves also with the same mind, for he who has suffered in the flesh has ceased from sin, that he no longer should live the rest of his time in the flesh for the lusts of men, but for the will of God” (1 Pet. 4: 1,2)
Waggoner, Waggoner on Romans, pp. 12, 13