Here are the pertinent passages of the Bible:
Matthew, Chapter 19
And it came to pass when Jesus had ended these words, he departed from Galilee and came into the coasts of Judea, beyond Jordan. 2 And great multitudes followed him: and he healed them there. 3 And there came to him the Pharisees tempting him, saying: Is it lawful for a man to put away his wife for every cause? 4 Who answering, said to them: Have ye not read, that he who made man from the beginning, made them male and female? And he said: 5 For this cause shall a man leave father and mother, and shall cleave to his wife, and they two shall be in one flesh. 6 Therefore now they are not two, but one flesh. What therefore God hath joined together, let no man put asunder. 7 They say to him: Why then did Moses command to give a bill of divorce, and to put away? 8 He saith to them: Because Moses by reason of the hardness of your heart permitted you to put away your wives: but from the beginning it was not so. 9 And I say to you, that whosoever shall put away his wife, except it be for fornication, and shall marry another, committeth adultery: and he that shall marry her that is put away, committeth adultery. 10 His disciples say unto him: If the case of a man with his wife be so, it is not expedient to marry. 11 Who said to them: All men take not this word, but they to whom it is given. 12 For there are eunuchs, who were born so from their mothers womb: and there are eunuchs, who were made so by men: and there are eunuchs, who have made themselves eunuchs for the kingdom of heaven. He that can take, let him take it.
1 Et factum est, cum consummasset Jesus sermones istos, migravit a Galilæa, et venit in fines Judææ trans Jordanem, 2 et secutæ sunt eum turbæ multæ, et curavit eos ibi. 3 Et accesserunt ad eum pharisæi tentantes eum, et dicentes: Si licet homini dimittere uxorem suam, quacumque ex causa? 4 Qui respondens, ait eis: Non legistis, quia qui fecit hominem ab initio, masculum et feminam fecit eos? Et dixit: 5 Propter hoc dimittet homo patrem, et matrem, et adhærebit uxori suæ, et erunt duo in carne una. 6 Itaque jam non sunt duo, sed una caro. Quod ergo Deus conjunxit, homo non separet. 7 Dicunt illi: Quid ergo Moyses mandavit dare libellum repudii, et dimittere? 8 Ait illis: Quoniam Moyses ad duritiam cordis vestri permisit vobis dimittere uxores vestras: ab initio autem non fuit sic. 9 Dico autem vobis, quia quicumque dimiserit uxorem suam, nisi ob fornicationem, et aliam duxerit, mœchatur: et qui dimissam duxerit, mœchatur. 10 Dicunt ei discipuli ejus: Si ita est causa hominis cum uxore, non expedit nubere. 11 Qui dixit illis: Non omnes capiunt verbum istud, sed quibus datum est. 12 Sunt enim eunuchi, qui de matris utero sic nati sunt: et sunt eunuchi, qui facti sunt ab hominibus: et sunt eunuchi, qui seipsos castraverunt propter regnum cælorum. Qui potest capere capiat.
1 Corinthians Chapter 7
7 For I would that all men were even as myself. But every one hath his proper gift from God: one after this manner, and another after that. 8 But I say to the unmarried and to the widows: It is good for them if they so continue, even as I. 9 But if they do not contain themselves, let them marry. For it is better to marry than to be burnt.
7 Volo enim omnes vos esse sicut meipsum: sed unusquisque proprium donum habet ex Deo: alius quidem sic, alius vero sic. 8 Dico autem non nuptis, et viduis: bonum est illis si sic permaneant, sicut et ego. 9 Quod si non se continent, nubant. Melius est enim nubere, quam uri.
32 But I would have you to be without solicitude. He that is without a wife is solicitous for the things that belong to the Lord: how he may please God. 33 But he that is with a wife is solicitous for the things of the world: how he may please his wife. And he is divided. 34 And the unmarried woman and the virgin thinketh on the things of the Lord: that she may be holy both in body and in spirit. But she that is married thinketh on the things of the world: how she may please her husband. 35 And this I speak for your profit, not to cast a snare upon you, but for that which is decent and which may give you power to attend upon the Lord, without impediment. 36 But if any man think that he seemeth dishonoured with regard to his virgin, for that she is above the age, and it must so be: let him do what he will. He sinneth not if she marry.
32 Volo autem vos sine sollicitudine esse. Qui sine uxore est, sollicitus est quæ Domini sunt, quomodo placeat Deo. 33 Qui autem cum uxore est, sollicitus est quæ sunt mundi, quomodo placeat uxori, et divisus est. 34 Et mulier innupta, et virgo, cogitat quæ Domini sunt, ut sit sancta corpore, et spiritu. Quæ autem nupta est, cogitat quæ sunt mundi, quomodo placeat viro. 35 Porro hoc ad utilitatem vestram dico: non ut laqueum vobis injiciam, sed ad id, quod honestum est, et quod facultatem præbeat sine impedimento Dominum obsecrandi. 36 Si quis autem turpem se videri existimat super virgine sua, quod sit superadulta, et ita oportet fieri: quod vult faciat: non peccat, si nubat.
It's not my intent to paste the whole of the Bible here, nor am I a Bible scholar, but this should answer your inquiry into the basis of such beliefs.
To the rest of you, my apologies. I do not wish to turn this forum into a pulpit, from which to preach the Gospel. That is not my place, nor is this the place for it. OT has asked, and I have answered, I will post no more lengthy Bible passages here.
I asked several posts ago to stop this, or move it to the "Debate" folder. This is not the place....