No illustration can fully communicate the Trinity, because the Trinity is God and always transcends the created order in essence, persons, and relationships. But as long as teachers make clear that every analogy will be to some extent inadequate, it may still be profitable to use these improper illustrations to explain why and how they fall short as adequate representations of the Trinity. By understanding that the Trinity is not like the three states of H20 (ice, water, vapor), the student learns to reject modalism. By learning that the Trinity is not like the three leaves of a single clover, he eschews partialism. By grasping that the Trinity is not like the light and heat emanating from the sun, he disclaims Arianism.
John MacArthur