Love flows from a heart that has first learned to receive the love of God and give it back to Him. Loving the Lord with all our heart, soul, strength, and mind is key to loving others. If it wasn't, then why did Jesus, the Son of God, instruct us in this way?
You see, when asked what was the greatest commandment, Jesus responded by telling us to love the Lord with everything we've got. (Matthew 22:37) We can't do that if we are unwillingly to receive His love for us first.
The Lord loves us. These may be words we say, but do we believe it? Do we truly comprehend His love for us? Do we realize that we manifest the Lord when we love like Him, and we can't do that if we've withheld ourselves from first receiving His love. We love like Him when we believe Him about His love for us.
We can truly love others when the love of Jesus has been born within us. His love is patient, kind, not rude, not arrogant, or not self-seeking. His love believes all things, hopes all things, and endures all things. His love never fails.
We can love like this when we learn to truly abide in His love for us. His love can then flow from us to others.