Change "Proceed to PayPal" Text on Checkout Button in WooCommerce

gistfile1.php

/* Change the "Proceed to PayPal" button text in the WooCommerce checkout screen
 * Add this to your theme's functions.php file
 */
add_filter( 'gettext', 'custom_paypal_button_text', 20, 3 );
function custom_paypal_button_text( $translated_text, $text, $domain ) {
	switch ( $translated_text ) {
		case 'Proceed to PayPal' :
			$translated_text = __( 'NEW BUTTON TEXT', 'woocommerce' );
			break;
	}
	return $translated_text;
}