Parallel
Genesis 38:9
Rahlfs Septuagint (1935) · Berean Standard Bible
γνοὺς δὲ Αυναν ὅτι οὐκ αὐτῷ ἔσται τὸ σπέρμα ἐγίνετο ὅταν εἰσήρχετο πρὸς τὴν γυναῖκα τοῦ ἀδελφοῦ αὐτοῦ ἐξέχεεν ἐπὶ τὴν γῆν τοῦ μὴ δοῦναι σπέρμα τῷ ἀδελφῷ αὐτοῦ
But Onan knew that the offspring would not belong to him; so whenever he would sleep with his brother’s wife, he would spill his seed on the ground so that he would not produce offspring for his brother.