וַתֹּ֣אמֶר לֵאָ֗ה נָתַ֤ן אֱלֹהִים֙ שְׂכָרִ֔י אֲשֶׁר־נָתַ֥תִּי שִׁפְחָתִ֖י לְאִישִׁ֑י וַתִּקְרָ֥א שְׁמ֖וֹ יִשָּׂשכָֽר׃
And Leah said: ‘God hath given me my hire, because I gave my handmaid to my husband. And she called his name Issachar.
Read kabbalistic (mystical) interpretation of Genesis 30:18: and classical mystical sources.