One of the differences between vows and soul contracts is that vows is a promise that we are making or given to our self.
Even when we vow to god to not do harm and we say it in public it is still something that we do inside. We do it to our self.
Soul contracts are about relationship.
About the connection we have to each other and the lessens that we came to learn.
Soul contracts are part of our Karma. They are part of our path in this life.
Vows are not necessarily a part of our karma.
Yet they influence it and help or disturb the karma.
When we work on vows it's a work between us and our soul.
When we work on soul contracts, we work on us and the person we have difficulty with.
And working on each of them creates a change within us and the way we conduct ourselves in the world