And the king shall do according to his will; and he shall exalt himself, and magnify himself above every god, and shall speak marvellous things against the GOD of gods, and shall prosper till the indignation be accomplished: for that that is determined shall be done. Neither shall he regard the God of his fathers, nor the desire of women, nor regard any god: for he shall magnify himself above all. But in his estate shall he honour the God of forces: and a god whom his fathers knew not shall he honour with gold, and silver, and with precious stones, and pleasant things. (Daniel 11:36-38)
When the Holy Spirit and the Church is out of the way (at some future date) the Antichrist will be introduced and given reign to become the 'ruler' of this world. Then salvation will still be by faith in Christ, but obedience will cost; either in unable to buy or sell, or loss of life. But those saved will be saved to the end. The better alternative is to be saved and obedient now, and secure in Christ instead of fearing the Antichrist who shall come.
GOD calls everyone to be saved now. Today is the day of salvation, the appointed time. Don't put it off, thinking you'll have plenty of time.
And if you are already saved, be the witness that GOD commands.