Jesus continues to teach his disciples.

## ravens ##

This refers either to 1) crows, a kind of bird that eat mostly grain, or 2) ravens, a kind of bird that eat the flesh of dead animals. Jesus' audience would have considered the ravens worthless because they could not be eaten.

## How much more valuable you are than the birds! ##

This is an exclamation, emphasizing the fact that people are much more valuable to God then birds.

## add a cubit to his lifespan ##

This is a metaphor because a cubit is a measure of length, rather than of time. The image is of a person's life stretched out as if it were a board, a rope, or some other physical object. (See: [[rc://en/ta/man/translate/figs-metaphor]])