Комментарий к Берешит 38:16

ויט אליה אל הדרך AND HE TURNED UNTO HER BY THE WAY — from the road he was following he turned to the road where she was. In old French détourner; English to turn aside.

כי לא ידע כי כלתו היא, he did not even recognise her after he joined her in her private quarters. Had he recognised her he would surely have spoken to her concerning why he had not given her to his surviving son. G’d has His own agenda; clearly, it was His wish that Tamar bear a child or two children sired by Yehudah who in His eyes was more acceptable than his son Shelah [whose mother‘s antecedents we know little about.] G’d wanted that the eventual Messiah should have had genetic material dating back to Tamar.

ויט אליה, he detoured in her direction from the direction he had been walking.
אל הדרך, to the beginning of the path where she was sitting, there being an opportunity nearby to enjoy privacy.