The Obligation of Sincerity in Calling to Allah the Exalted

The Shaykh : In this is evidence for the obligation of sincerity: that you call to the path of Allah. This is sincerity. This is because the callers have intentions regarding people; some call to the path of Allah, but out of revenge against the one being called, or to vindicate their own opinion. Does the one who calls out of revenge against the one being called, or to vindicate his own opinion, count as a caller to Allah or to the path of Allah? No. There are people now who call to Allah, but they want to vindicate their own statement. Therefore, it is very difficult for them to retract it, even if it contradicts the truth, because they want the words to be theirs or the authority of opinion to be theirs. This is undoubtedly far removed from sincerity entirely. This is calling to desire, not calling to guidance.
Another person calls out of revenge against the individual; this is also wrong. It is obligatory to call to Allah, to the path of Allah, to reform the servants of Allah, not out of revenge against them, nor to vindicate your opinion, but to reform them. And if that is the case, meaning for the reform of creation, the person will take the closest paths to achieving the intended goal.