The Creator of the universe says that even our prayers are an abomination if we do not love His Law (His instructions on how all men are to live).
One who turns away his ear from hearing the law, even his prayer is an abomination. (Pro 28:9)
Then they will cry to Yehovah, but He will not hear them; He will even hide His face from them at that time, because they have been evil in their deeds. (Mic 3:4)
The sacrifice of the wicked is an abomination to Yehovah, but the prayer of the upright is His delight. The way of the wicked is an abomination to Yehovah, but He loves him who follows righteousness. (Pro 15:8-9)
But there is one prayer that Yehovah will always hear; the prayer of a broken spirit and a contrite heart.
The sacrifices of God are a broken spirit, a broken and a contrite heartâ€” These, O God, You will not despise. (Psa 51:17)
Here is a great video on the prayer that Yehovah will always hear.