All the principles of Arya Samaj are based on reasoning and not on superstition. When we test this reason we find it to be a big superstition. Therefore Arya Samaj never seeks any good or bad omen in performing weddings. Therefore whichever day suits you is a good day for your
Arya Samaj marriage. When God has made all days equal then we, human beings cannot control which day is better than the other.
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