In VS §14, the Pope writes affirms the essential connection between the two great commandments.
Both the Old and the New Testaments explicitly affirm that without love of neighbour, made concrete in keeping the commandments, genuine love for God is not possible. Saint John makes the point with extraordinary forcefulness: “If anyone says, ‘I love God’, and hates his brother, he is a liar; for he who does not love his brother whom he has seen, cannot love God whom he has not seen” (Jn 4:20 [sic; should be 1 Jn 4:20]) [emphasis in original].
Once again it’s worth pointing out the connection between eternal life and obedience. Because the love in view here isn’t comfy-cozy feelings of affection; it’s love that is expressed in action, as St James reminds us:
And if a brother or sister be naked and want daily food: And one of you say to them: Go in peace, be warmed and filled; yet give them not those things that are necessary for the body, what shall it profit? [Jas 2:15-16]
To say that what a Christian does has no effect on his standing before God is flatly contrary to the Word of God and Christian morality.