Who said that, the religion was highly practical and sternly ethical?

Chaitanya
Namadeva
Guru Nanak
Kabir

The correct answer is: Guru Nanak.

Guru Nanak Dev Ji was the founder of Sikhism, a monotheistic religion that emphasizes the oneness of God and the equality of all people. He was born in Punjab, India, in 1469 and died in 1539.

Guru Nanak was a social reformer who spoke out against the caste system and other social injustices. He also emphasized the importance of living a simple and ethical life.

His teachings are recorded in the Guru Granth Sahib, the holy book of Sikhism.

Chaitanya Mahaprabhu was a Hindu saint and reformer who lived in the 16th century. He was born in Bengal, India, and is considered to be the founder of the Gaudiya Vaishnava tradition.

Chaitanya Mahaprabhu emphasized the importance of devotion to Krishna, a Hindu deity. He also preached a message of love, compassion, and tolerance.

Namadeva was a Hindu saint and poet who lived in the 13th century. He was born in Maharashtra, India, and is considered to be one of the most important saints of the Bhakti movement.

Namadeva emphasized the importance of devotion to God. He also wrote many devotional songs and poems.

Kabir was a Hindu-Muslim mystic poet who lived in the 15th century. He was born in Kashi, India, and is considered to be one of the most important saints of the Bhakti movement.

Kabir emphasized the importance of love and devotion to God. He also wrote many devotional songs and poems.

In conclusion, the correct answer is: Guru Nanak.