Not a rabbi but I could play one on TV...
Mystically, in the works of Kabbalah and Chassidut, pro-creation is being a partner with G-d. To take part in this act, akin to creating ‘something from nothing,’ touches the essence of pleasure, so it flows from there that it [is pleasurable, etc....]
Biggirl, from one of your posts (ie, JC and the Church....) you might say, ahem, G-d and the Jewish people.
Re: Go forth.... a little joke: Why is the first commandment given from G-d to man “go forth and multiply?” Because when man saw how fun the first commandment is, he’d want to keep ALL of the commandments! (rim shot, please)
“Applause and laughter!”
Thank you and most excellent!