The Lord confirmed His covenant with Abram by commanding him to circumcise all the males in his household. Circumcision thereby became the physical demonstration (sign) of the obedient faith of Abram and his descendants.510God further encouraged the patriarch's faith by changing Abram's name to Abraham and Sarai's to Sarah. This was an added confirmation that God would indeed give them innumerable seed as He had promised.
"This chapter is a watershed in the Abraham story. The promises to him have been unfolded bit by bit, gradually building up and becoming more detailed and precise, until here they are repeated and filled out in a glorious crescendo in a long and elaborate divine speech. From this point in Genesis, divine speeches become rarer and little new content is added to the promises, but the fulfillment of these promises becomes more visible."511
Abram undoubtedly assumed that Ishmael would be the promised heir until God told him that Sarai would bear his heir herself (v. 16). That revelation is the most important feature of this chapter. God gave the name changes and circumcision to confirm the covenant promise of an heir and to strengthen Abram's faith.
Thirteen years after the birth of Ishmael (16:16) God spoke to Abram again (the fifth revelation; v. 1). God called Himself by a new name: El Shaddai (the Almighty God). This was appropriate in view of the thing God proceeded to reveal to Abram that He would do. It would require supernatural power.
The references to the "covenant"in this chapter have caused some confusion. The Abrahamic Covenant (ch. 15) is in view (vv. 4, 7, 11, 19, 21) but also the outward sign of that covenant that was the covenant of circumcision (vv. 2, 9, 10, 13, 14). Thus Moses used the word "covenant"with two different references here. Whereas the Abrahamic Covenant was unconditional, the covenant of circumcision depended on Abram's obedience (vv. 1-2). God would bless Abram as Abram obeyed God by circumcising his household. This blessing would be in the form of multiplying Abram's descendants "exceedingly,"even more than God had already promised.
The rite of circumcision was to be a continuing sign of the Abrahamic Covenant to all of Abram's descendants. God also gave Abram and Sarai the added assurance that they would have a multitude of descendants by changing their names.512
Abram(high or exalted father) -- Abraham(father of a multitude)
Sarai(my princess) -- Sarah(royal princess [from whom kings would come, v. 16])
Abraham's name emphasized the number of his seed. Sarah's evidently stressed the royal nature of their line (vv. 6, 16, 20; cf. 12:2).
"The choice of the word be fruitfulin verse 6 and multiplyin verse 2 seems intended to recall the blessing of all humankind in 1:29: Be fruitful and multiply and fill the land,' and its reiteration in 9:1: Be fruitful and multiply and fill the land.' Thus the covenant with Abraham was the means through which God's original blessing would again be channeled to all humankind."513
God wanted Abraham to circumcise his male servants as well as his children. The reason was that the Abrahamic Covenant would affect all who had a relationship with Abraham. Consequently they needed to bear the sign of that covenant. The person who refused circumcision was "cut off"from his people because by refusing it he was repudiating God's promises to Abraham.
"This expression undoubtedly involves a wordplay on cut. He that is not himself cut (i.e., circumcised) will be cut off (i.e., ostracized). Here is the choice: be cut or be cut off."514
There are two views as to the meaning of being cut off from Israel. Some scholars hold it means excommunication from the covenant community and its benefits.515However the better evidence points to execution sometimes by the Israelites but usually by God in premature death.516The threat of being cut off hung over the Israelite offender as the threat of a terminal disease that might end ones life at any time does today.
The person who refused to participate in circumcision demonstrated his lack of faith in God by his refusal. Thus he broke the covenant of circumcision (v. 14).
Only males underwent circumcision, of course. In the patriarchal society of the ancient Near East people considered that a girl or woman shared the condition of her father if she was single, or her husband if she was married.
Circumcision was a fitting symbol for several reasons.
1. It would have been a frequent reminder to every circumcised male of God's promises involving seed.
2. It involved the cutting off of flesh. The circumcised male was one who repudiated "the flesh"(i.e., the simply physical and natural aspects of life) in favor of trust in Yahweh and His spiritual promises.
3. It resulted in greater cleanliness of life and freedom from the effects of sin (i.e., disease and death).
Circumcision was not a new rite. The priests in Egypt practiced it as did most of the Canaanites and the Arabs, but in Mesopotamia it was not customary. Later the Edomites, Moabites, and Ammonites practiced it, but the Philistines did not.517By commanding it of Abraham and his household God was giving further evidence that he would bless the patriarch. Circumcision has hygienic value since cancer of the penis has a much higher incidence in uncircumcised males.518Circumcision was a rite of passage to adulthood in these cultures.519Normally it was practiced on young adults (cf. ch. 34). Circumcising infants was something new.
"Designating the eighth day after birth as the day of circumcision is one of the most amazing specifications in the Bible, from a medical standpoint. Why the eighth day?
"At birth, a baby has nutrients, antibodies, and other substances from his mother's blood, including her blood-clotting factors, one of them being prothrombin. Prothrombin is dependent on vitamin K for its production. Vitamin K is produced by intestinal bacteria, which are not present in a newborn baby. After birth prothrombin decreases so that by the third day it is only 30 percent of normal. Circumcision on the third day could result in a devastating hemorrhage.
"The intestinal bacteria finally start their task of manufacturing vitamin K, and the prothrombin subsequently begins to climb. On day eight, it actually overshoots to 110 percent of normal, leveling off to 100 percent on day nine and remaining there for the rest of a person's healthy life. Therefore the eighth day was the safest of all days for circumcision to be performed. On that one day, a person's clotting factor is at 110 percent, the highest ever, and that is the day God prescribed for the surgical process of circumcision.
"Today vitamin K (Aqua Mephyton) is routinely administered to newborns shortly after their delivery, and this eliminates the clotting problem. However, before the days of vitamin K injections, a 1953 pediatrics textbook recommended that the best day to circumcise a newborn was the eighth day of life.520
"Research indicates that other Middle Eastern cultures practiced circumcision . . . However, the Hebrews were unique in that they practiced infant circumcision, which, though medically risky if not properly performed, is less physically and psychologically traumatic than circumcisions performed at an older age."521
God has not commanded circumcision of the flesh for Christians. Some Christians in the reformed traditions of Protestantism regard baptism as what God requires of us today in place of circumcision. They practice infant baptism believing that this rite brings the infant into the "covenant community"(i.e., the church) and under God's care in a special sense. Some believe baptism saves the infant. Others believe it only makes the infant a recipient of special grace. The Bible is quite clear, however, that baptism is a rite that believers should practice after they trust Christ as their Savior as a testimony to their faith. There are parallels between circumcision and baptism, but God did not intend baptism to replace circumcision. God did command circumcision of the Israelites in the Mosaic Law, but He has not commanded it of Christians. We do not live under the Mosaic Law (Rom. 4:10-13; 6:14-15; 7:1-4; 10:4).
Abraham's laugh (v. 17) seems to have been a joyful response to God's promise.522Sarah's laugh (18:15) seems to have arisen from a spirit of unbelief. The basis of this distinction is God's response to the two laughs.
The writer's use of the phrase "the very same day"(v. 26) points to a momentous day, one of the most important days in human history (cf. Noah's entry into the ark, 7:13; and the Exodus, Exod. 12:17, 41, 51).
The fifth revelation from God advanced God's promises in five particulars.
1. Part of God's blessing would depend on Abraham's maintaining the covenant of circumcision though the Abrahamic Covenant as a whole did not depend on this (vv. 1-2).
2. Many nations would come from Abraham (vv. 4-6).
3. The Abrahamic Covenant would be eternal (vv. 7-8).
4. God would be the God of Abraham's descendants in a special relationship (vv. 7-8).
5. Sarah herself would bear the promised heir (v. 16).523
"Abraham's experiences should teach us that natural law [barrenness] is no barrier to the purposes and plans for [sic] God."524
"Thus Abraham and Noah are presented as examples of those who have lived in obedience to the covenant and are thus blameless' before God, because both obeyed God as he commanded them' (17:23; cf. 6:22; 7:5, 9, 16)."525
God requires a sanctified life of those who anticipate His promised blessings.
