Thought attracts that upon which it is directed.
These repetitive words and phrases are merely methods of convincing the subconscious mind.
Repetition of the same chant, the same incantations, the same affirmations leads to belief, and once that belief becomes a deep conviction, things begin to happen.
What you believe yourself to be, you are.
We usually get what we anticipate.
Happiness is a 'state of mind' which we ourselves have the power to control - and that control lies in our thinking.