The phrase "茶亦忘" can be translated and understood in a few different ways depending on the context, but it generally means "tea is also forgotten" or "even tea is forgotten." It combines three Chinese characters:

茶 (cha, tea)
亦 (yi, also, even)
忘 (wang): Forget

An image comes to mind of a tea cup left on a desk, forgotten as one becomes absorbed in their thoughts or activities. The tea has cooled, symbolizing a mind preoccupied with deep contemplation, caught in a meditative flow state. This scroll sets the tone for deep thinking and meditation, encouraging wholehearted and earnest dedication to one's tasks. For this scroll, there are three immediate interpretations of this tripartite phrase "茶亦忘" as follows: 

Forgetting Simple Joys: It suggests that someone is so caught up in other things that they even forget to enjoy their tea.
Beyond Everyday Pleasures: It implies that a person has moved beyond everyday comforts, like drinking tea, to focus on something deeper or more important.
Deep Thinking: It might refer to a state where someone is so absorbed in deep thoughts or meditation that they set aside usual activities, such as having tea.