Firstly: The Ruling of the Prayer
The five daily prayers are an individual obligation for every legally competent Muslim. Consensus has been quoted on this by: Ibn Hazm, Ibn Rushd, al-Nawawi, and Ibn Taymiyyah.
Secondly: The Ruling of the One Who Abandons the Prayer Denying Its Obligation
Whoever leaves the prayer out of denial that it is an obligation, then he has disbelieved. Consensus has been quoted on this matter by: Ibn `Abd al-Barr, al-Nawawi, and Ibn Taymiyyah.
Thirdly: The Ruling of the One Who Abandons the Prayer Completely Out of Laziness and Neglect
The one who leaves the prayer completely out of laziness and neglect is a disbeliever and is outside the fold of Islam. This is the position of the Hanbalis,  The position of the Hanbalis is that the one who abandons the prayer is not excommunicated from the fold of Islam until the Imam invites him to pray first, with the condition that the time for the second prayer is too tight to perform it. More deserving of excommunication, therefore, is the one who completely abandons it. a position among the Shafi`is, a position among Malikis, the position of a group from the Salaf, and the majority of scholars of Hadith. It is also the view of Ibn Taymiyyah and Ibn al-Qayyim, and it is the choice of Ibn `Uthaymin.
Fourthly: The Punishment of the One Who Abandons the Prayer
The one who abandons the prayer is sentenced to death penalty. This is the position of the majority:  While there is still a difference between those who follow that position: is he killed out of punishment or for apostasy? Malikis and Shafi`is opine that he is killed as a punishment, whereas the Hanbalis hold the position he is killed for apostasy. Malikis, Shafi`is, and Hanbalis.