Tyndale Open Study NotesGenesis 17

God gave Abram's family signs that his promises would come true. He changed Abram's name to Abraham (17:1–8). He established circumcision as the sign of the covenant (17:9–14, 23–27). He changed Sarai's name to Sarah (17:15–22).

• God Almighty (Hebrew El-Shaddai): This name for God emphasizes his power (see also 28:3; 35:11; 43:14; 48:3; 49:25).

• Walk before Me and be blameless: To bless the nations, Abram needed to obey. Almighty God would guide his actions.

God guaranteed his promise by changing Abram’s name. Abram means “exalted father.” This referred to his father Terah and his noble lineage (11:27). His new name, Abraham (Hebrew ’ab hamon), means "father of a multitude." This was a wordplay on the promise of his countless descendants (see also John 8:31–59; Romans 4:16–17; Galatians 3:7, 15–19, 29). Whenever the new name was used, he and his household would remember that a multitude of nations would come from him.

kings will descend from you: This is the first sign that Israel would become a nation ruled by kings (see also 35:11; 36:31; Numbers 24:7; Deuteronomy 17:14–18; 28:36).

The land of Canaan was to be an everlasting possession for the descendants of Abraham. The Lord would always be their God (see Jeremiah 31:31–40; Zechariah 8:8; Luke 1:68–79; Revelation 21:1–4).

God gave circumcision as a confirming sign that reminded all households of loyalty to the covenant.

will be cut off: This punishment seems to have several applications. A person could be exiled from society or put to death by the community; most often it warned that a person might die prematurely (see Exodus 31:14; Leviticus 7:20–27; 17:3–4; 20:17–18; 23:28–29; Numbers 15:30–31; see also Psalm 31:22; Ezekiel 21:4; Romans 9:3; 11:22).

Failure to be circumcised was a serious violation of the covenant (see Exodus 4:24–26; compare Galatians 5:2–4).

Sarah’s new name marked an important step in her calling (God’s purpose for her life). It fit her role as the future mother of kings and pointed to God’s promise.

he laughed (Hebrew yitskhaq): This was because the promise seemed unbelievable. He thought his family line would continue through Ishmael. But Abraham and Sarah would have their own son.

The name Isaac (Hebrew yitskhaq) means “he laughs.” This recalls Abraham's disbelief when he heard God's promise. It also reminds us of God's favor and pleasure at Isaac's birth (compare 21:6).

God would not abandon Ishmael. His family would prosper (see 25:13–16). But the covenant promises were for Isaac.

After God spoke to Abraham about Isaac, Abraham followed God's instructions immediately. He performed circumcision as a sign of faith, showing their participation in the covenant (compare Romans 4:11–12; Galatians 5:2–6, 11; 6:15; Philippians 3:2–3; Colossians 2:11–12; 1 Peter 3:21).