Tendai, also known as Japanese Tiantai, is a school of Buddhism that was founded by the Chinese monk, Zhiyi, in the 6th century. It is based on the teachings of the Lotus Sutra and emphasizes the concept of "one vehicle" or the idea that all beings have the potential to attain enlightenment.

In Tendai, the concept of karma is viewed as an integral part of the Buddhist teachings. Karma, in this context, refers to the actions and intentions of an individual that have consequences in this life and the next. Tendai teaches that every action, whether it is physical, verbal, or mental, has an effect on one's life and the lives of others.

According to Tendai, karma is not seen as a form of punishment or reward, but rather as a natural law that governs the universe. This means that every individual is responsible for their own actions and the consequences that follow. Tendai also emphasizes the idea of interdependence, which means that all beings are interconnected and every action has a ripple effect on the world around us.

One of the key teachings of Tendai is the concept of "three thousand realms in a single moment of life." This means that every moment, we have the potential to experience three thousand different states of existence, ranging from the highest state of enlightenment to the lowest state of suffering. These states are determined by our karma, which is constantly changing based on our actions and intentions.

Tendai also teaches that karma is not fixed and can be transformed through the practice of Buddhist teachings. By cultivating wisdom and compassion, individuals can change their karma and create a more positive future for themselves and others. This is known as "changing poison into medicine," a concept that is central to Tendai's teachings.

In Tendai, the ultimate goal is to break free from the cycle of karma and attain enlightenment. This is achieved through the practice of the Lotus Sutra and the teachings of the Threefold Truth, which include the principles of emptiness, temporary existence, and the Middle Way.

In conclusion, Tendai views the concept of karma as a natural law that governs the universe and is closely intertwined with the teachings of interdependence and the Threefold Truth. It emphasizes the importance of taking responsibility for one's actions and the potential for transformation through the practice of Buddhist teachings.