A.T. Robertson Commentary James 2:23

"and the scripture was fulfilled which saith, And Abraham believed God, and it was reckoned unto him for righteousness; and he was called the friend of God." — James 2:23 (ASV)

Was fulfilled (επληρωθη). First aorist passive indicative of πληροω, the usual verb for fulfilling Scripture. So James quotes Ge 15:6 as proving his point in verse 21 that Abraham had works with his faith, the very same passage that Paul quotes in Ro 4:3 to show that Abraham's faith preceded his circumcision and was the basis of his justification. And both James and Paul are right, each to illustrate a different point.

And he was called the friend of God (κα φιλος θεου εκληθη). First aorist passive indicative of καληο. Not a part of the Scripture quoted. Philo calls Abraham the friend of God and see Jubilees 19:9; 30:20. The Arabs today speak of Abraham as God's friend. It was evidently a common description before James used it, as in Isa 41:8; 2 Chronicles 20:7.