We have to
believe that Allah (Exalted and Glorified be He) is above the Throne in Heaven. One of the manifestations of complete slavery to Allah (Glorified be He) is to worship Him as if you see Him and though you see Him not, verily Allah sees you. What you have mentioned concerning doubtful matters and suspicions which make a Muslim imagine that he worships a vacuum, is out of Satan's handiwork and temptations. A Muslim should put an end to these matters and stop thinking about them. He should observe Dhikr (Remembrance) of Allah (Exalted be He) abundantly, seek refuge with Him from the accursed Satan and do deeds that can benefit him in his religion and his life of this world. It is permissible for a Mu'min (believer), when observing Salah (Prayer), to believe that Allah is in front of him though He (Glorified be He) is above His Throne. In this respect, the Prophet (peace be upon him) says:
If anyone of you stands up (Part No. 2; Page No. 410) after finishing Salah (Prayer), he should not spit neither in front of him, nor to his right, but he could spit to his left or under his feet
Agreed upon Hadith. Spitting to the left is permissible only outside the Masjid (mosque). If anyone is in the Masjid, he can only spit on the end of his outer garment, in his handkerchief or the like; for the Messenger (peace be upon him) said:
Spitting in the mosque is a sin...
May Allah grant us success. May peace and blessings be upon our Prophet Muhammad, his family, and Companions.