Mat 19:5 And said, For this cause shall a man leave father and mother,

Mat 19:5 And said, For this cause shall a man leave father and mother, and shall cleave to his wife: and they twain shall be one flesh?

This is a great example of a verse that explains how Christ uses certain words symbolically to express his unique view of reality from outside our normal time perspective.

Here, Christ uses the term "flesh" to symbolize our temporary connections in this life between people. In Greek, the term means "the physical order of things" as opposed to the spiritual. Christs used of symbols regarding the realms of the temporary and the eternal are discussed here and the cycle of transformation between them here.  In this verse, Christ describes the progression of our key relationships: from the physical flesh (the realm of the physical)  of our parents to the union of emotional flesh (the realm of relationships) with our spouses.

Christ distinguishes between the life that we are given at birth and the life we create through our choices and actions. Using another example, his symbol from the physical body is "bread," which is eaten and turned becomes the physical body. In marriage, the physical body is transformed into the emotional life.

The transformation cycle works on many levels: flesh creates relationships (marriage) and relationships create more flesh (children). Bread creates the physical body (through eating) and the physical body creates more bread (through work). Thus our relationships with other people become part of us and the product of our work is also part of us.

This transformation is outside of time from Christ's perspective. Our existence is extended over time through the people we touch and the products we create and, in turn, our existence is made possible over time through the people who touch us and the products that they create.

"Cause" is from heneka, which means "on the account of," "because of," and "for the sake of."

"Leave" is from kataleipô, which means "to be left," "left behind," "forsake," "abandon," "leave," and "remaining."

"Cleave" is from proskollaô, which means "to glue to or on," and "to be stuck to."

"Twain" is from duo (dyo), which means "two."

"One" is from heis (heis), which means "one," "single," and "one and the same." This adjective is irregular, having a number of forms depending on sex, number, and case: heis, henos, heni, hen, hena, mia, mias, miai, mian; hen, henos, hen. The form here is mia, feminine singular.

"Flesh" is sarx (sarx), which means "flesh," "the body," "fleshy," "the pulp of fruit," "meat," and "the physical and natural order of things" (opposite of the spiritual or supernatural).