This is once again a baseless allegation of the non Ahmadi Muslims which is taken out of context. This has been beautifully answered by the Promised Messiah Hazrat Mirza Ghulam Ahmad(as) in his book “Divine Manifestations”. The Promised Messiah(as) states:
“Likewise, in the following revelation, I was given the glad tidings of the spread of Islam through me. God addressed me saying: that is, ‘O Moon and O Sun! You are of Me and I am of you.’ In this Divine Revelation, God has first called me the moon and given Himself the title of the Sun. This means that just as the moon receives its glow through the bounty and benevolence of the sun, so is my light a result of the bounty and beneficence of God. Then God has called Himself the Moon and named me the sun. This indicates that He will manifest His glorious light through me. He was hidden, but shall now be manifested through me. The world was unaware of His radiance, but now, through me, His awe-inspiring light will spread all over the world. Just as a bolt of lightning illuminates the whole sky in a flash, so shall all this come to pass in this age” (Divine Manifestations pages 4-5)
The Promised Messiah(as) has also said:
“O Moon! O Sun! You are from Me and I am from you.” Anyone can construe these words to mean whatever he likes, but their true meaning is that God first made me the ‘Moon’, for, like the Moon, I was manifested through the True Sun; thereafter, He became the ‘Moon’, for the light of His Glory shone through me and will continue to do so (Fountain of Christianity, page 54)