I like to think of it as touching the side of the boat that is your only way of keeping from drowning. You aren’t in the boat, the operation of saving you is not complete, but you would sink, were the boat not there. Your salvation has arrived, and all those truly saved are present there with you, making your salvation possible. Yet you are not in the boat yet, because you could yet choose to refuse your salvation. After all, though we must be clean to enter Heaven, it is impossible without the work of Heaven that we be cleansed. Heaven must touch us as we are in order for us to be able to enter Heaven. This is the great glory of the Incarnation, that God reached out to us and loved us and touched us while we were yet sinful, not worthy to touch him nor able to do it. We always approach Heaven in just that poverty.
Underline mine:
From the Catechism:
1419 *Having passed from this world to the Father, Christ gives us in the Eucharist the pledge of glory with him. Participation in the Holy Sacrifice identifies us with his Heart, sustains our strength along the pilgrimage of this life, makes us long for eternal life, and unites us even now to the Church in heaven, the Blessed Virgin Mary, and all the saints. *
From Sacramentum Caritatis, Apostolic Exortation of Pope Benedict XVI:
The Eucharist: a gift to men and women on their journey
30. If it is true that the sacraments are part of the Church’s pilgrimage through history (99) towards the full manifestation of the victory of the risen Christ, it is also true that, especially in the liturgy of the Eucharist, they give us a real foretaste of the eschatological fulfilment for which every human being and all creation are destined (cf. Rom 8:19ff.). Man is created for that true and eternal happiness which only God’s love can give. But our wounded freedom would go astray were it not already able to experience something of that future fulfilment. Moreover, to move forward in the right direction, we all need to be guided towards our final goal. That goal is Christ himself, the Lord who conquered sin and death, and who makes himself present to us in a special way in the eucharistic celebration. Even though we remain “aliens and exiles” in this world (1 Pet 2:11), through faith we already share in the fullness of risen life. The eucharistic banquet, by disclosing its powerful eschatological dimension, comes to the aid of our freedom as we continue our journey.
The eschatological banquet
31. Reflecting on this mystery, we can say that Jesus’ coming responded to an expectation present in the people of Israel, in the whole of humanity and ultimately in creation itself. By his self-gift, he objectively inaugurated the eschatological age. Christ came to gather together the scattered People of God (cf. Jn 11:52) and clearly manifested his intention to gather together the community of the covenant, in order to bring to fulfilment the promises made by God to the fathers of old (cf. Jer 23:3; Lk 1:55, 70). In the calling of the Twelve, which is to be understood in relation to the twelve tribes of Israel, and in the command he gave them at the Last Supper, before his redemptive passion, to celebrate his memorial, Jesus showed that he wished to transfer to the entire community which he had founded the task of being, within history, the sign and instrument of the eschatological gathering that had its origin in him. Consequently, every eucharistic celebration sacramentally accomplishes the eschatological gathering of the People of God. For us, the eucharistic banquet is a real foretaste of the final banquet foretold by the prophets (cf. Is 25:6-9) and described in the New Testament as “the marriage-feast of the Lamb” (Rev 19:7-9), to be celebrated in the joy of the communion of saints (100).