"The Mimamsaka philosophers, following the principles of Jaimini, stress fruitive activity and say that if there is a God, He must be under the laws of fruitive activity. In other words, if one performs his duties very nicely in the material world, God is obliged to give one the desired result. According to these philosophers, there is no need to become a devotee of God. If one strictly follows moral principles, one will be recognized by the Lord, who will give the desired reward. Such philosophers do not accept the Vedic principle of bhakti-yoga. Instead, they give stress to following one's prescribed duty."
Caitanya-caritamrta, Madyam lila 25:56
"Mimamsaka means they have decided that "There is no necessity of worshiping God. If there is any God, all right, you do your duty nicely, and He will be obliged to award you the required result. Then there is no question of flattering Him." That is mimamsaka philosophy. Just like in government, there are so many departments. So you need not to flatter him, but you do your duty, you pay your tax, you abide by the laws, then everything will be right. You need not worship any person. That is their philosophy, mimamsa karma-mimamsa. Everyone is... Under the spell of karma, everyone is suffering or enjoying as the result of his past deeds. So the karma-mimamsaka philosopher says, "There is no necessity of worshiping God. You do your duty." Just like some moralists say that "What is the use of God, God, Hare Krsna? Just do your duty." But he does not know that what is his duty. The duty is only to worship God, and nothing more. That is the duty. All other duties are maya's spell only. There is no other duty. Because this human life is meant for that duty. The animals cannot execute that duty. Only the human being. Therefore our only duty is to understand God and engage ourself in that way."
Srila Prabhupada Lecture on Caitanya-caritamrta, 01-24-67, San Francisco
"One class of philosophers, known as Mimamsakas, represented by sages such as Jaimini, have concluded that everyone should be engaged in pious activities or prescribed duties and that such activities will lead one to the highest perfection. But this is contradicted in the Ninth Chapter of Bhagavad-gita, where Lord Krsna says that by pious activities one may be elevated to the heavenly planets, but as soon as one's accumulation of pious activities is used up, one has to leave the enjoyment of a higher standard of material prosperity in the heavenly planets and immediately come down again to these lower planets, where the duration of life is very short and where the standard of material happiness is of a lower grade. The exact words used in the Gita are ksine punye martya-lokam visanti. Therefore the conclusion of the Mimamsaka philosophers, that pious activities will lead one to the Absolute Truth, is not valid. Although a pure devotee is by nature inclined to pious activities, no one can attain the favor of the Supreme Personality of Godhead by pious activities alone. Pious activities may purify one of the contamination caused by ignorance and passion, but this is automatically attained by a devotee who is constantly engaged in hearing the transcendental message of Godhead in the form of the Bhagavad-gita, Srimad-Bhagavatam or similar scriptures. From the Bhagavad-gita we understand that even a person who is not up to the standard of pious activities but who is absolutely engaged in devotional service is to be considered well situated on the path of spiritual perfection. It is also said in the Bhagavad-gita that a person who is engaged in devotional service with love and faith is guided from within by the Supreme Personality of Godhead. The Lord Himself as Paramatma, or the spiritual master sitting within one's heart, gives the devotee exact directions by which he can gradually go back to Godhead. The conclusion of the Mimamsaka philosophers is not actually the truth which can lead one to real understanding."
Krsna Book, Chapter 87
Bhaktivedanta Book Trust. HDG A.C. Bhaktivedanta Swami Srila Prabhupada.