The כרובים
The כרובים, known as Cherubs, placed on the Holy Ark has a very mystical nature. They were angelic figures that had the faces of children.
They represented innocence and purity. This was the appropriate place to place them, as the Ark, similarly, was all holiness and purity.
It was fairly often that the curtains, or פרוכת, was left open, and people could see inside the Holy of Holies. Magically, the כרובים supplied the gauge to let the nation know if Hashem was pleased with them. When things were right, the כרובים faced one another, and the wings touched. If Hashem was not pleased, the wings separated, and the faces turned away from one another.
When the first Temple was destroyed, (there was no ארון קודש in the second Temple), the evil Babylonians found the כרובים embracing, as a symbol that the Jewish people would be separated from G-d as they went into Exile. It was comparable to two lovers saying good-by before being faced with a long separation.
Aside from being very mystical, the כרובים were a clear indication of Hashem’s love and closeness to עם ישראל.