Praise be to Allaah.
If only one man is praying with the imam, then he should
stand to the imam’s right, and not on his left, because of the hadeeth of
Ibn ‘Abbaas (may Allaah be pleased with him), who stayed overnight with his
maternal aunt Maymoonah (may Allaah be pleased with her); the Prophet
(peace and blessings of Allaah be upon him) got up to pray qiyaam al-layl,
and Ibn ‘Abbaas stood on his left, and he reached behind him and made him
stand on his right. This indicates that if only one person is praying behind
the imam, he should stand on the right and not on the left.
But if more than one person is praying behind the imam, then
they should stand behind him, and the right side of the row is better than
the left. This applies if the two sides of the row are similar, but if the
right side of the row is clearly stretching further than the left, then
being on the left and closer to the imam is better.
Based on this, the people praying behind the imam should not
all be on the imam’s right to the extent that there is no one on his left
except one or two men. That is because what is prescribed in the case of
three men is that the imam should be between them, with one man on his right
and one on his left; they should not all be on his right. This indicates
that the imam should be in the middle of the row or thereabouts.
To sum up: the right is better if the sides are equal or
close to that. But if the right hand side stretches further, then the left
is better, because it is closer to the imam. End quote.