This is a superscription that tells about the psalm. Some scholars say that this is part of the scripture and some say that it is not. (See "What are Superscriptions in Psalms" in [Introduction to Psalms](../front/intro.md).)
The word "ears" adds emphasis to the statement that they have heard and understood the things that the writer is about to describe. The writer addresses this statement to God. Alternate translation: "God, we have heard clearly" (See: [[rc://en/ta/man/jit/figs-idiom]])
Both of these phrases use the word "days" to refer to the time period when the ancestors of the people of Israel were alive. (See: [[rc://en/ta/man/jit/figs-parallelism]])