大乘起信論裂網疏 4.75

4.75

因該果海名如來藏，亦可名為理即法身。果徹因源名為法身，亦可名為究竟如來藏也。初顯示體相竟。

Because the cause encompasses the ocean of fruition, it is called the tathāgatagarbha, and may also be called the Dharmakāya of principle-identity. Because the fruition reaches the source of the cause, it is called the Dharmakāya, and may also be called the ultimate tathāgatagarbha. The first [part], revealing the essence and attributes, is finished.