The Athanasian Creed states:

Whosoever will be saved, before all things it is necessary that he hold the catholic faith. Which faith except every one do keep whole and undefiled; without doubt he shall perish everlastingly. And the catholic faith is this: That we worship one God in Trinity, and Trinity in Unity; Neither confounding the Persons; nor dividing the Essence. . . . He therefore that will be saved, let him thus think of the Trinity.

Furthermore, it is necessary to everlasting salvation; that he also believe faithfully the Incarnation of our Lord Jesus Christ. . . . This is the catholic faith; which except a man believe truly and firmly, he cannot be saved.

I think the biblical basis is easy to establish for the idea that believing the incarnation is necessary for salvation, but what biblical basis can be found that believing in the Trinity is necessary for salvation?

The Athanasian Creed states:

Whosoever will be saved, before all things it is necessary that he hold the catholic faith. Which faith except every one do keep whole and undefiled; without doubt he shall perish everlastingly. And the catholic faith is this: That we worship one God in Trinity, and Trinity in Unity; Neither confounding the Persons; nor dividing the Essence. . . . He therefore that will be saved, let him thus think of the Trinity.

Furthermore, it is necessary to everlasting salvation; that he also believe faithfully the Incarnation of our Lord Jesus Christ. . . . This is the catholic faith; which except a man believe truly and firmly, he cannot be saved.

I think the biblical basis is easy to establish for the idea that believing the incarnation is necessary for salvation, but what is the biblical basis for the idea that believing in the Trinity is necessary for salvation?