Genesis 21:3

And Abraham called the name of his son that was born unto him, whom Sarah bare to him, Isaac [literally, "laughter"].

(Geneva Bible) - And Abraham called his son’s name that was born unto him, which Sarah bare
him, Isaac.

(Scofield ref Bible)  Sara, type of grace, free woman, and of "Jerusalem which is above"

Isaac is typical in a fourfold way:

1.  Of the church as composed of the spiritual children of Abraham (Gal iv 28

2.  Of Christ as the son "obedient unto death" Gen xxii. 1-10, Phil ii 5-8

3.  Christ as the Bridegroom of the called out bride (Gen 24)

4.  Of the new nature of the believer as "born after the spirit" (Gal IV 29)