וַיְבָ֧רֶךְ אֹתָ֛ם אֱלֹהִ֖ים לֵאמֹ֑ר פְּר֣וּ וּרְב֗וּ וּמִלְא֤וּ אֶת־הַמַּ֙יִם֙ בַּיַּמִּ֔ים וְהָע֖וֹף יִ֥רֶב בָּאָֽרֶץ׃
And God blessed them, saying: ‘Be fruitful, and multiply, and fill the waters in the seas, and let fowl multiply in the earth.’
Read kabbalistic (mystical) interpretation of Genesis 1:22: and classical mystical sources.