מְלֵאָתְךָ֥ וְדִמְעֲךָ֖ לֹ֣א תְאַחֵ֑ר בְּכ֥וֹר בָּנֶ֖יךָ תִּתֶּן־לִּֽי׃
Thou shalt not delay to offer of the fulness of thy harvest, and of the outflow of thy presses. The first-born of thy sons shalt thou give unto Me.
Read kabbalistic (mystical) interpretation of Exodus 22:28: and classical mystical sources.