A vocation is a personal call from God. Pope Benedict XVI has explained it this way:

The Lord has his plan for each of us, he calls each one of us by name. Our task is to be listeners, capable of perceiving his call, to be courageous and faithful, so that we may follow him, and in the end, be found as trustworthy servants who have used well the gifts entrusted to us.

Before the creation of the world, before our coming into existence, the heavenly Father chose us personally, calling us to enter into a filial relationship with him, through Jesus, the Incarnate Word, under the guidance of the Holy Spirit (World Day of Prayer 4/23/09).