SAMPLES:  these are what is said by the officiant just before the exchange of rings.
IRV1
The circle is the symbol of the sun and the earth and the universe. It is a symbol of holiness and of perfection and peace. In these rings (this ring) it is the symbol of unity, in which your two lives are now joined in one unbroken circle, in which, wherever you go, you will always return unto one another to your togetherness.
IRV 2
The ring symbolizes the unbroken circle of endless love, it is worn on the third finger because of an ancient Greek belief that a vein from that finger connected directly to the heart, thus symbolizing the depth and sincerity of love.
IRV 3
The vows you make are a statement of intent and commitment. They cannot endure unless you make them endure. The spoken word holds no hidden power within itself, for human ingenuity has never yet devised a vow which cannot be broken. We have developed law and conscience, even pride, as keepers of our sacred pledges, but we have also found ways to mitigate each one. So it is not simply to words or to institutions that we appeal at this moment of commitment, but to the resources upon which you can draw from within yourselves.
IRV4
The wedding ring is a symbol of the unbroken circle of love. Love freely given has no beginning and no end, no giver and no receiver for each of you is the giver and each is the receiver. May this ring remind you both of the vows, which you have freely taken.