يُولِجُ اللَّيْلَ فِي النَّهَارِ وَيُولِجُ النَّهَارَ فِي اللَّيْلِ وَسَخَّرَ الشَّمْسَ وَالْقَمَرَ كُلٌّ يَجْرِي لِأَجَلٍ مُسَمًّى ۚ ذَٰلِكُمُ اللَّهُ رَبُّكُمْ لَهُ الْمُلْكُ ۚ وَالَّذِينَ تَدْعُونَ مِنْ دُونِهِ مَا يَمْلِكُونَ مِنْ قِطْمِيرٍ
He makes the night pass into the day and makes the day pass into the night, and He has disposed the sun and the moon, each moving for a specified term. That is Allah, your Lord; to Him belongs all sovereignty. As for those whom you invoke besides Him, they do not control so much as the husk of a date stone. (Holy Qur’an, Surah Al-Fatir, 35:13)
وَيَعْبُدُونَ مِنْ دُونِ اللَّهِ مَا لَا يَضُرُّهُمْ وَلَا يَنْفَعُهُمْ وَيَقُولُونَ هَٰؤُلَاءِ شُفَعَاؤُنَا عِنْدَ اللَّهِ ۚ قُلْ أَتُنَبِّئُونَ اللَّهَ بِمَا لَا يَعْلَمُ فِي السَّمَاوَاتِ وَلَا فِي الْأَرْضِ ۚ سُبْحَانَهُ وَتَعَالَىٰ عَمَّا يُشْرِكُونَ
They worship besides Allah that which neither causes them any harm, nor brings them any benefit, and they say, ‘These are our intercessors with Allah.’ Say, ‘Will you inform Allah about something He does not know in the heavens or on the earth?’ Immaculate is He and exalted above [having] any partners that they ascribe [to Him]! (Holy Qur’an, Surah Yunus, 10:18)
أَلَا لِلَّهِ الدِّينُ الْخَالِصُ ۚ وَالَّذِينَ اتَّخَذُوا مِنْ دُونِهِ أَوْلِيَاءَ مَا نَعْبُدُهُمْ إِلَّا لِيُقَرِّبُونَا إِلَى اللَّهِ زُلْفَىٰ إِنَّ اللَّهَ يَحْكُمُ بَيْنَهُمْ فِي مَا هُمْ فِيهِ يَخْتَلِفُونَ ۗ إِنَّ اللَّهَ لَا يَهْدِي مَنْ هُوَ كَاذِبٌ كَفَّارٌ
Indeed, only exclusive faith is worthy of Allah, and those who take other as awliya’ besides Him [claiming] ‘We only worship them so that they may bring us near to Allah,’ Allah will judge between them concerning that about which they differ. Indeed Allah does not guide someone who is a liar and an ingrate. (Holy Qur’an, Surah Al-Zumar, 39:3)
These ayahs pertain to authority of God over universe, His exclusive worship and faith in Him. All Muslims or followers of any monotheistic divine religions believe that the whole universe is created by God and all its affairs are under the total authority of God. No follower of monotheistic divine religion takes anyone besides God as a partner in His authority.
Paying respect to Prophets and awliya’ (saints or divine personalities) doesn’t mean worshipping them. Any authority exercised or miracle shown by Prophets and awliya’ is because God has bestowed them special powers and they are not independent in their authority or power. These miracles include giving shifa (restoring health), shaqq Al-qamar, dividing the moon into two halves, shafa’a (interceding for the sins), bringing dead to life again etc.
Visiting the graves of dead and addressing them is the sunnah of Prophet (S). Remembering the dead and saluting them is the sunnah of Prophet and Ayahs of Qur’an mention those who have passed before. Commemorating the days of birth and death of Prophet and awliya’ is mentioned in Qur’an and sunnah of Prophet.
Seeking help from creatures of God either alive or those who are bestowed with life after death such martyrs doesn’t mean worshipping them or taking them as partners in the authority of God.
Weeping over dead relatives or beloved of God such as Prophets, awliya’ and martyrs is mentioned in Qur’an and is a sunnah of prophet.