To be worthy of divine love, the creature must be capable of loving, and actually love Love Itself. Furthermore, for angels and men to love God it was not enough that they love merely as angels and men, which could be only a natural love. God created angels and men because He could transform them into beings who coud love Him as He loves Himself. We might say that He demanded that they love Him as equals. They must love Him with a divine love, what we call a supernatural love. In Catholic parlance, the word 'supernatural' always refers to that which is possible only to God, or those to who God communicates a divine power.
Comment: A natural human can only receive this divine power within the Catholic Church initially through the Sacrament of Baptism with the result that if he dies as a baby he goes straight to heaven. If he does not die as a baby the only way he continues to receive God's divine power is through the remaining Sacraments. That is why there is no possibility of salvation outside of the One, Holy, Catholic and Apostolic Church.