The thing people often forget is that Jesus wrote nothing. Instead, he established a Church.
The Catholic Church wrote the "books" of the Bible and many many other writings. Then, the Catholic Church called conferences of bishops to decide which writings made it into the Bible. The Church did not surrender it's authority when it selected some of its writings for inclusion in the Bible. We need not look at a saying in the Bible and lament that there is no context for it. There is 2000 years of authoritative context.
People often lament that Catholics don't read the Bible enough. That is a worthy lament. But, I lament more that Catholics don't read the Catechism enough. The Catechism often directly addresses issues that are only peripherally addressed in the Bible, and Catholics are mislead when they start creating their own doctrine to fill in the gaps in their own knowledge. If any one has a question, I think there is a good chance that the question has been addressed by dozens of authoritative Church writings. The Bible is a good place to start. The Catechism is also a great place to start, but if you do start with the Bible, the Catecism is the obvious next step. And, the Catechism is heavily annotated, so other authoritative writings can be easily found which dig deep into particular issues.