The principles of the Bhagavad-gītā were spoken to Arjuna, and, for that matter, to other highly elevated persons, because he was highly advanced compared to ordinary persons in other parts of the world. Two plus two equals four is a mathematical principle that is true both in the beginner’s arithmetic class and in the advanced class as well. Still, there are higher and lower mathematics. In all incarnations of the Lord, therefore, the same principles are taught, but they appear to be higher and lower in varied circumstances.
In the center Square, Krishna is shown in His original two-handed form, holding a flute. Surrounding Him are ten of His eternal incarnations, pictured in the order in which they appeared in the material world, beginning clockwise from the lower left-hand corner.
a) Matsya, the fish incarnation, is saving the Vedas.
b) Kurma, the tortoise incarnation, is holding the hill on His back.
c) Varaha, the boar incarnation, is fighting with the demon Hiranyaksa.
d) Nrismhadeva, the lion incarnation, is killing the demon Hiranyakasipu.
e) Vamanadeva, the dwarf incarnation, is begging some land from King Bali.
f) Parasurama, is killing the demoniac ksatriyas.
g) Lord Ramacandra, is going off into exile with His Wife Sita, and brother, Laksmana.
h) Krishna, is lifting Govardhana Hill and beside His is His brother, Balarama.
i) Lord Buddha.
j) Lord Kalki is riding on His horse, killing all the demons and thus liberating them.
Bhagavad-gita As It Is – Macmillan 1972 Edition
By His Divine Grace A.C. Bhaktivedanta Swami Prabhupada
Chapter 4, Text 7
yadā yadā hi dharmasya
glānir bhavati bhārata
abhyutthānam adharmasya
tadātmānaṁ sṛjāmy aham
yadā—whenever; yadā—wherever; hi—certainly; dharmasya—of religion; glāniḥ—discrepancies; bhavati—manifested, becomes; bhārata—O descendant of Bharata; abhyutthānam—predominance; adharmasya—of irreligion; tadā—at that time; ātmānam—self; sṛjāmi—manifest; aham—I.
TRANSLATION
Whenever and wherever there is a decline in religious practice, O descendant of Bharata, and a predominant rise of irreligion-at that time I descend Myself.
The Hare Krishna Movement 