Its implied. When a husband and wife have a child, that creation is the love they have for wanting a child, the act of having the child, and taking care of him or her.
Likewise, in Gensis says God created man. He gave them what they needed to live with Him. That is love.
The common christian thought is that like parents who displine their child, so does God. It is done out of love, they say.
Love can also come from husband and wife relationship. As a wife is obedient to her husband (in some faiths) so as a person to God. That relationship is a form of love.
The holy spirit is love itself. Therefore, the devotion each prophet had to their God, in christianity, they were filled with thebHoly Spirit--the Love for God..the devotion to their faith "as a result" God loves them back in both OT and NT by giving Isrealites land being the chosen people. Abraham receieved what christians say the love from God by acting in obedience to sacrifice His own child.
Look at it from the Believer's perspective and not your own. There is love in the OT from the believers view AND that does not mean you and I experience it the same as believers to call it that.
EDIT
God's love in the OT
Love in the OT.
It makes sense from THEIR perspective and Not my own.