I say, and with God's help: The one who abandons prayer has two situations: either he leaves it out of denial or laziness. The first: the one who abandons prayer out of denial and rejection of it: he is a disbeliever; because prayer is an obligation established by definitive evidence, and whoever denies an obligation is a disbeliever. The second: the one who abandons prayer deliberately out of frivolity and laziness: he is a sinner, and he is to be detained until he prays; because he is detained for the right of the servant, and the right of God is more deserving. It was narrated by Ubadah that the Messenger of God (peace be upon him) said: "Five prayers that God has made obligatory upon His servants; whoever comes with them and completes them without neglecting them out of disdain for their rights, he will have a covenant with God to enter him into Paradise. And whoever comes with them and neglects them out of disdain for their rights, he will not have a covenant with God; if He wills, He will punish him, and if He wills, He will have mercy on him." This is in Sahih Ibn Hibban 5: 23, and the selected hadiths 8: 365, and Sunan Abu Dawood 2: 62, and Sunan al-Nasa'i al-Kubra 1: 142, and Al-Mujtabi 1: 230, and Sunan Ibn Majah 1: 449, and Al-Muwatta 1: 12. In another narration: "Whoever meets Him with them and does not neglect anything from them, he will have a covenant with Him to enter him into Paradise. And whoever meets Him and has neglected anything from them out of disdain for their rights, he will meet Him with no covenant; if He wills, He will punish him, and if He wills, He will forgive him," in Musnad Ahmad 5: 322, and Mushkil al-Athar 4: 194. And from Ka'b ibn Ujrah al-Ansari (may God be pleased with him) who said: "The Messenger of God (peace be upon him) came out to us while we were in the mosque, seven of us, three from our Arabs and four from our freedmen. He said: What is keeping you here? We said: Prayer. He said: Then he pointed with his finger to the ground, then he lowered it for a while, then he raised his head to us and said: Do you know what your Lord says? We said: God and His Messenger know best. He said: He says: Whoever prays the prayer at its time and establishes its limits, he will have a covenant with God that when he comes to Him, He will enter him into Paradise. And whoever does not establish the prayer at its time and does not establish its limits, he will not have a covenant with Me; if I wish, I will enter him into Hell, and if I wish, I will enter him into Paradise," in Mushkil al-Athar 4: 200, and Sunan al-Darimi 1: 303, and Musnad Abd ibn Hamid 1: 145. Imam al-Tahawi said in Mushkil al-Athar 4: 201: "And in both of their hadiths: And if He wills, He will enter him into Paradise, it indicates that this does not take him out of Islam to make him an apostate or a polytheist; because God, exalted be He, does not enter Paradise anyone who associates with Him; as He, exalted be He, says: {Indeed, whoever associates with Allah, then Allah has forbidden him Paradise} (Al-Ma'idah: 73), and He does not forgive him; as He, exalted be He, says: {Indeed, Allah does not forgive that partners should be associated with Him, but He forgives what is less than that for whom He wills} (An-Nisa: 48)." This is more appropriate by analogy; because God's obligations upon His servants are at specific times, including the five daily prayers, and among them is fasting the month of Ramadan. Whoever intentionally abandons fasting in the month of Ramadan without denying its obligation upon him is not a disbeliever nor an apostate from Islam; thus, the same applies to the one who abandons prayer until its time expires without denying it and disbelieving in it; he is not an apostate nor is he outside of Islam. Refer to: Mushkil al-Athar 4: 206, and Tanwir al-Absar and Al-Durr al-Mukhtar 1: 235, and God knows best.