This came up in a thread of Judas Iscariot having eternal life. One dispute was whether Judas was a believer or not.
The answer is both: A chosen apostle and believer, which is self explanatory. A son of perdition and unbeliever, which also speaks for itself. No one can be an unbelieving chosen apostle by Jesus, nor can anyone be a believing son of perdition condemned by Jesus.
And,. since no one can be a believer and unbeliever at the same time, then even as an unbeliever can be made a believer, so can a believer be made an unbeliever.
And this is what the Bible teaches, that belief is made unbelief by disobedience.
Heb 3:17
But with whom was he grieved forty years? was it not with them that had sinned, whose carcases fell in the wilderness? And to whom sware he that they should not enter into his rest, but to them that believed not? So we see that they could not enter in because of unbelief.
The children of Israel that sinned against the LORD are called unbelievers, that had by faith passed through the Red Sea, but by disobedience could not enter in to the promised land.
Heb 11:29
By faith they passed through the Red sea as by dry land: which the Egyptians assaying to do were drowned.
And so by faith in Jesus as the Christ and Son of God we pass from life unto death, but by disobedience we cannot enter into the promise of glory, that is only for them that obey Him:
Heb{5:8}
Though he were a Son, yet learned he obedience by the things which he suffered; And being made perfect, he became the author of eternal salvation unto all them that obey him;
And so we see, that Judas the believer made a chosen apostle by Jesus, made himself an unbeliever by betraying his Lord Jesus Christ to the accusers.
The answer is both: A chosen apostle and believer, which is self explanatory. A son of perdition and unbeliever, which also speaks for itself. No one can be an unbelieving chosen apostle by Jesus, nor can anyone be a believing son of perdition condemned by Jesus.
And,. since no one can be a believer and unbeliever at the same time, then even as an unbeliever can be made a believer, so can a believer be made an unbeliever.
And this is what the Bible teaches, that belief is made unbelief by disobedience.
Heb 3:17
But with whom was he grieved forty years? was it not with them that had sinned, whose carcases fell in the wilderness? And to whom sware he that they should not enter into his rest, but to them that believed not? So we see that they could not enter in because of unbelief.
The children of Israel that sinned against the LORD are called unbelievers, that had by faith passed through the Red Sea, but by disobedience could not enter in to the promised land.
Heb 11:29
By faith they passed through the Red sea as by dry land: which the Egyptians assaying to do were drowned.
And so by faith in Jesus as the Christ and Son of God we pass from life unto death, but by disobedience we cannot enter into the promise of glory, that is only for them that obey Him:
Heb{5:8}
Though he were a Son, yet learned he obedience by the things which he suffered; And being made perfect, he became the author of eternal salvation unto all them that obey him;
And so we see, that Judas the believer made a chosen apostle by Jesus, made himself an unbeliever by betraying his Lord Jesus Christ to the accusers.