Oxytocin is a neuropeptide.  It helps us feel safe and secure.  The release of oxytocin from the hypothalamus helps drop the level of cortisol stress hormones.  This also helps blood pressure drop.  A soothing and warm touch helps the process unfold.  It is not necessary to have touch, however.  The connection of your mind and heart to remembering that you are loved and connected also has a similar effect.  Dan Goleman in his book Social Intelligence speaks to how we can condition the release of oxytocin by putting ourselves in the proximity of people we feel safe and secure with.  There have also been studies that show that time with our pets, especially dogs, can help build and strengthen the release of oxytocin.  When we activate a memory or image in our mind, we activate the prefrontal cortex.  The feeling of being secure and loved within these images and memories will strengthen the circuits to release oxytocin.

Our relationship, bond, affection, and security in God are also rewarded by oxytocin.  Our love of God draws us toward altruism, security, bonding, and greater acceptance of outgroups; all features of increased levels of oxytocin.  Fr. Pedro Arrupe captures the effect well in this poem:

Nothing is more practical than 
finding God, that is, than 
Falling in Love 
in a quite absolute, final way. 
What you are in love with, 
what seizes your imagination, 
will affect everything. 
It will decide 
what will get you out of bed in the morning, 
what you do with your evenings, 
how you spend your weekends, 
what you read, whom you know, 
what breaks your heart, 
and what amazes you with joy and gratitude. 
Fall in love, stay in love, 
and it will decide everything.