Actually, it is quite religious...it's described perfectly as a covenantal exchange, an exchange of persons.   Does the following sound familiar to you:  "I shall be your God and you shall be my people".  That's covenantal.   And that provides the basis or essence for the Catholic Church's conception of marriage. 

Here are just a few examples.

Genesis 17:8
Exodus 29:45
Leviticus 26:45
Ezekiel 14:11
Zechariah 8:8
2 Corinthians 6:16
Hebrews 8:10
Jeremiah 32:38
Ezekiel 11:20
Ezekiel 37:23
Jeremiah 7:23
Jeremiah 31:33
Ezekiel 37:27
Jeremiah 31:1
Revelation 21:3
Exodus 6:7
Leviticus 26:12
Revelation 21:7
Jeremiah 11:4