CCC 2218 The fourth commandment reminds grown children of their responsibilities toward their parents. As much as they can, they must give them material and moral support in old age and in times of illness, loneliness, or distress. Jesus recalls this duty of gratitude.1
For the Lord honored the father above the children, and he confirmed the right of the mother over her sons. Whoever honors his father atones for sins, and whoever glorifies his mother is like one who lays up treasure. Whoever honors his father will be gladdened by his own children, and when he prays he will be heard. Whoever glorifies his father will have long life, and whoever obeys the Lord will refresh his mother.2
O son, help your father in his old age, and do not grieve him as long as he lives; even if he is lacking in understanding, show forbearance; in all your strength do not despise him. .. Whoever forsakes his father is like a blasphemer, and whoever angers his mother is cursed by the Lord.3
1 Cf. Mk 7:10-12.
2 Sir 3:2-6.
3 Sir 3:12-13, 16.