By far the most popular Wedding Reading to be used in a Religious Ceremony is from the New Testament Letter of St. Paul:

 

A Reading from the First Letter of St Paul to the Corinthians

"Be ambitious for the higher gifts. And I am going to show you a way that is better that any of them.

If I have all the eloquence of men or of angels, but speak without love, I am simply a gong booming or a cymbal clashing. If I have the gift of prophecy, understanding all the mysteries there are, and knowing everything, and if I have faith in all its fullness, to move mountains, but without love, then I am nothing at all. If I give away all that I possess, piece by piece, and if I even let them take my body to burn it, but am without love, it will do me no good whatever.

Love is always patient and kind; it is never jealous; love is never boastful or conceited; it is never rude or selfish; it does not take offence, and is not resentful. Love takes no pleasure in other people's sins but delights in the truth; it is always ready to excuse, to trust, to hope, and to endure whatever comes.

Love does not come to an end."

Corinthians 1:13

 

"As the Father has loved me, so have I loved you. Now remain in my love. If you obey my commands, you will remain in my love, just as I have obeyed my Father's commands and remain in his love.

I have told you this so that my joy may be in you and that your joy may be complete. My command is this: Love each other as I have loved you. Greater love has no one than this, that he lay down his life for his friends.

You are my friends if you do what I command. I no longer call you servants, because a servant does not know his master's business. Instead, I have called you friends, for everything that I learned from my Father I have made known to you.

You did not choose me, but I chose you and appointed you to go and bear fruit—fruit that will last. Then the Father will give you whatever you ask in my name. This is my command: Love each other.

John 15:9-17