Praise be to Allah.
An action cannot be an act of worship unless it includes two things: complete love and complete humility. Allaah says (interpretation of the meaning):
“But those who believe, love Allaah more (than anything else)”
“Verily, those who live in awe for fear of their Lord”
And Allaah mentions them together in the aayah (interpretation of the meaning):
“Verily, they used to hasten on to do good deeds, and they used to call on Us with hope and fear, and used to humble themselves before Us” [al-Anbiya’ 21:90]
Once this is understood, we will realize that worship can only be accepted from a Muslim who believes in Allaah alone (Tawheed), as Allaah says (interpretation of the meaning):
“And We shall turn to whatever deeds they (disbelievers, polytheists, sinners) did, and We shall make such deeds as scattered floating particles of dust” [al-Furqaan 25:23]
In Saheeh Muslim (214) it is narrated that ‘Aa’ishah (may Allaah be pleased with her) said: “I said, ‘O Messenger of Allaah, during the Jaahiliyyah, Ibn Jud’aan used to uphold the ties of kinship and feed the poor. Will that avail him anything?’ He said, ‘It will not avail him anything because he never said, “O Allaah, forgive me my sins on the Day of Judgement”’” – i.e., he did not believe in the resurrection or do good deeds hoping to meet Allaah.
Moreover, the Muslim’s worship will not be accepted unless it meets two basic conditions:
1 – Sincerity of intention towards Allaah, which means that the person’s intention in all his words and deeds, both outward and inward, is to seek the pleasure of Allaah and none other.
2 – It should be in accordance with the sharee’ah which Allaah has prescribed, and he should not worship Allaah in any other way. That is achieved by following the Prophet (peace and blessings of Allaah be upon him) and what he brought, and shunning anything that goes against it, and not inventing any new form of worship that has not been narrated in sound reports from the Prophet (peace and blessings of Allaah be upon him).
The evidence for these two conditions is the aayah (interpretation of the meaning):
“So whoever hopes for the Meeting with his Lord, let him work righteousness and associate none as a partner in the worship of his Lord” [al-Kahf 18:110]
Ibn Katheer (may Allaah have mercy on him) said: “ ‘So whoever hopes for the Meeting with his Lord’ means his reward; ‘let him work righteousness’ means, that which is in accordance with the laws of Allaah; ‘and associate none as a partner in the worship of his Lord’ this means seeking the Face of Allaah alone, with no partner or associate. These two conditions are the basis of acceptable deeds, which must be sincerely for the sake of Allaah alone and correct according to the sharee’ah of the Messenger of Allaah (peace and blessings of Allaah be upon him).