In short, the fathers teach us that while faith and hope are important, it is only Love that ultimately saves us. For Christ himself says, 'He who loves me keeps my commandments'.
While faith and hope may bring one to Christ, it is only Love which keeps the person joined to him and abiding in him. Faith without works is dead, or so says the apostle James, so faith and hope are perfected by Love, and the thing which perfects is greater than the things perfected.
Thus the one who hopes and has faith may be brought to Christ, but it is only the one who loves that endures until the end, and thus is ultimately saved. Paul emphasizes this in saying, 'I may have all faith and know all sciences and mysteries, but if I have not love, I am nothing.'
And finally, if God is love, as the apostle John says, then to truly have love is to truly have God. To have him is to participate in him, which is, as we are taught, the substance of salvation. As Peter says, 'Be ye partakers of the divine nature.'
It should also be noted that while faith and hope are necessary before we have come into the new heavens and new earth, they are not necessary after we have received the thing we believed we would have and hoped for. Then, only love persists.