This blessing for the consumption of meat (or poultry, or fish) is based on a verse from Vayikra / Leviticus, ch. 17: כִּי נֶפֶשׁ הַבָּשָׂר בַּדָּם הִוא וַאֲנִי נְתַתִּיו לָכֶם עַל־הַמִּזְבֵּחַ לְכַפֵּר עַל־נַפְשֹׁתֵיכֶם כִּי־הַדָּם הוּא בַּנֶּפֶשׁ יְכַפֵּר׃ (“For the life of the flesh is in the blood. And as for me, I have given it to you on the alter to ransom your lives, for it is the blood that ransoms in exchange for life.”) This verse helps us remember (and how can we ever forget?!) that any bloodshed, is a loss of life – human or animal. And, it helps us understand that even when we kill for our own sustanance (or even in a ritual offering), we cause a loss of life. The burden is on us. We are commanded to release the blood-life so we can use the meat. (I wrote more in detail about this blessing here.)