1 John 4:8

He that loveth not, knoweth not God
If a man loves not the children of God, those that are born of him, he does not know, so as to love God, the Father of them; for to pretend love to God, the begetter of them, whom he sees not, and not love those who are begotten by him, and are visible objects of respect, is a contradiction, and cannot be reconciled: see ( 1 John 4:20 ) . This clause is left out in the Ethiopic version, and is transposed in the Syriac version, which reads the text thus, "for God, is love, and whoever loveth not, knoweth not God". By which reading, the following reason stands in close connection with ( 1 John 4:7 ) .

For God is love;
he loves himself; there is an entire love between the three divine Persons, who are in the strictest, and in the most inconceivable and inexpressible manner affected to each other; their love is natural and essential: God loves all his creatures as such, nor does he hate any of them, as so considered; and he bears an everlasting, unchangeable, and invariable love to his elect in Christ Jesus; of which an instance is given in the following verses, and is a reason why the saints should love one another; that they might be like their heavenly Father, by whom they are begotten, and of whom they are born, and whose children they are; seeing he is love itself, and in his breast is nothing else but love. So the Shekinah is, by the Cabalistic Jews ^F20, called (hbha) , "love".